I will collect a list of games that have been used for this purpose (with or without modification), planned revisions or releases. This link is pretty good if you scroll down to the table top list, but it is not complete, and like anything in the internet universe, it is subject to the whims of the "Gremiln Gods of the Cyberspace", so I'll copy and paste at least the pertinent list here.
Role playing games
Victorian Adventure Enthusiast Victorian RPG Guide
Victoriana 2nd Edition RPG
Sorcery and Steam D20 RPG
Dragon MechD20 System RPG
Historical Hobbies GASLIGHT RPG
The Steampunk Project RPG
The Victoruisand blog
Kallisti Press Full Light, Full Steam
Victoriana from Heresy Gaming
TatterHood Online RPG
Hollow Earth Expedition from Exile Games
Iron Kingdoms from Privateer Press
Forgotten FuturesA rather nice RPG, you can even play a dog as player character!
Broken Gears RPG
OGL Steampunk RPG
Superheroes of the Steampunk Age RPG
Unhallowed Metropolis RPG
Castle Fankestien RPG
GURPS Steampunkby Steve Jackson Games
In the mean time, I would like to discuss modification and use of my own creation "Slayers Guild" previously labeled "Monsters and Slayers" which is being modified for Gaslight and/or Steampunk use. Slayers Gyuild aka Monsters and Slayers is a table top role playing game that was developed as a direct response to repeated requests from traditional Dungeons and Dragons players during the time of Advanced Dungeons and Dragons 2nd edition. They consistently asked for something with more realism and fewer charts and graphs so as to speed up gameplay. The problem was that more realism almost always meant using more charts and graphs or slowing down play to account for more realistic variables.
In spite of this, I found a solution that works very well. In the traditional D&D world, better armor meant less liklihood of an arrow or sword hitting someone. There are many far fetched explanations for this, but the fact is that it was an early attempt to make better armor desirable adn likely to slow down damage. Let me say that I honor the early achievements fo such genius game designers, but the point is that many fans of that system wanted something that more directly reflected reality. In this area I researched hit probability likelihood by putting my own flesh on the line with the help of some rather fanatical Society of Creative Anachronisms members who showed me the hard way how even a fairly quick and nimble person would get hit and bruised a lot by a well trained swordsman, but that shields would greatly reduce the number of injurious hits, and that the bigger the shield, the less often they could sneak around it. The bruises on my flesh clearly attested to this (along with historical surveys of ancient treatises on the subject as well as historical weapons research from other sources.)
Armor, on the other hand, as common sense would suggest, had no effect on hit probability whatever other than possibly to increase hit likelihood if it became heavy enough to make the wearer slow to dodge. It did; however, have such an enormous advantage in terms of damage received that knights in full armor became the time period equivalent of tanks, and historical treatises clearly state that little short of great 2 handed weapons, specifically axes and maces, were effectively pretty useless against them. That was at least until heavy crossbows came along with a full block and tackle style windlass to crank them up to armor piercing levels.
As such, I changed the entire combat system to reduce hit likelihood based entirely on what my modern military manuals state as the most essential factors, namely range, cover, and concealment. Range is self explanatory. cover is anything sturdy enough to totally stop the weapon and reduce damage received to zero, including shields if they are of heavy enough material for the projectile in question. Concealment refers to anything (magick or otherwise) that makes it harder to see the target and thus reduces aiming effectiveness. If they cannot be seen at all, a hit becomes unlikely, but not entirely impossible, if the shooter has a good guess where his target lies.
The other problem was that in the original system, warriors, and other could increase the total amount of damage their bodies could take prior to death, or actually prior to having any negative effect on them what so ever. (at least in the 2nd edition rules) A such they could elevate to a level where say 40 or 50 arrows might not actually slow them down, cause their aim to be worsened, their strength affected, or have any effect at all, but simply stubbing their toe or getting a small scratch, if they were down to the last hit point of health, would drop them dead as a stone. This also meant they could became capable of receiving a catapult shot, ballistae bolt, or the magickal equivalent of an anti-tank missile directly to the head and appear essentially unaffected by the damage. At some point this becomes unpalatable for many players. Yes, I have heard the far fetched explanations for this as well about slowing wearing the person down etc., but in game terms it still means thatthey could take a large cannonball in the face (assuming it was one of the odd games where black powder weapons existed such as some I was in) without it being any great problem.
What is more, the excitement is lost if life and death struggles often are so risk free that it requires extraordinary superhuman feats on the part of the bad guys plus a total cessation of any and all laws of physics or even of magick, to actually kill any of the player's characters even if they are being unusually stupid that day. Of course this is only true of the mostly highly developed of player characters, but these are not so rare as you would think among people with the amount of play time and experience we had in those days. I actually had some assassins for instance, that were only around levels 7, 8, and 9 respectively that could meet out over 50 points of damage per round in most situations and the weakest one died only when a trusted member of her own party attacked her, while already damaged, from behind with a 20 die fireball in a ring. This is because she had such excellent protective magicks and enchanted items that it was nearly impossible to kill her if she knew you were trying to do so. That is what I mean about getting to a point where the excitement is somehow lost. The players were so well equipped that I only played them on very special assignments and they were otherwise relegated to non-player characters and semi-demigods at a surprisingly low level.
I overcame this very easily by simply limiting the total number of points any character could recieve to a direct factor of their endurance aka constitution score. As Slayers Guild uses a hit point system that is about 10:1 of what is normal for D&D, that means 100 time their constitution or endurance score. That score rises slowly with adventuring and exercise, but rapidly hits maximum and cannot exceed the racial max for any reason including God Granted options. As such heavy armor is the only way player characters become able to wade through an army of little guys without taking much damage, but that is a very accurate recreation, actually, of historical warfare back in the days when the nobles both determined who won the battle by looking to see who ran out of peasants first. In fact they expected knights to be so far above actually dying, most of the time, that they got the Pope to outlaw the use of heavy crossbows, because it allowed commoners to be able to actually kill, fairly easily, a noble knight, and that was clearly against God's plan for the universe, in their opinion at least.
In addition to this, when damage is received, if it exceeds 10% of the player's normal maximu, then 2 six sided dice are rolled. One dictates if the hit is to left arm, left leg, right leg, torso, or head& neck region and the other states if any special effects occur, but is applicable only to torso and head/neck hits. those can kill in a single blow regardless of level, armor etc, albeit well armored characters don't usually recieve 10% of hit points in a single blow. They could also cause scarring, loss of an eye (plus minus 1 to ranged attacks), double damage plus loss of consciousness for 1-12 rounds, or triple damage and instant death on a head/neck wound. On a torso critical hit, they could get no extra damage, a punctured lung (extra 1 d6 damage per round), Double damage plus 1 d6 per round from an organ hit, or triple damage and instant death from a hit to the heart. A critical hit to the weapon arm reduces rolls to hit by one, on the shield arm it reduces shield effectiveness against hand-held weapons, and even leg hits affect both rate of movement and dodging ability. As all of this takes effect immediately, any really significant wound has a very clearly visualized injury with very detailed and significant effects on the character, the battle, and the story line they are weaving as a group. As such the game master can give a very descriptive image about each critical wound based on his own knowledge of what would be likely to result from that type of weapon to that part of the body struck from the direction in question and causing the result listed on the dice.
As such all critical hit injuries can be very individualized using a single roll of 2 six sided dice a single time. After a little practice, most game masters can do this without consulting any chart at all as the dice are two different colors and the outcomes follow a logical pattern with higher numbers causing the most damage to the worst area. Did I mention that doing over 50% in one hit removed arms, legs, or head? Of course magick can reverse most things, but a missing head is a hard rap to get around. It's also a little harder to explain carrying characters home in pieces to the guild and trying to arrange the level of repair required for that one. Even a raise dead is not enough if their head is detached, much less if it goes missing all together.
I would now like to explain how I am modifying this game to produce a Gaslight and a Stempunk Variation of the game. The difference is simply that Gaslight modification keeps the excessively fantasy oriented magick spell list and historically common fantasy creatures that exist in all human Junginan archetypal subconscious and are found listed in any dictionary such as bubbears, orcs vampires etc. In the Steampunk modification the magickal system still exists, but the spell list is limited exclusively to psychic abilities that have been documented as real, if very unusual abilities documented in at least some respectable research studies. This would include things that are difficult to publish, but have historical documentation such as astral projection, mental suggestion to "not see someone" which is the real world equivalent of invisibility, etc. As I am unusually well educated in both the science and the art of such things, and have decades of experience using such techniques, I do feel qualified to differentiate between "Real" and fantasy, but I acknowledge that what I consider fantasy, may also be proven as real someday, just not yet.etc.
I also have to add more than a few vehicle types such as airships, biplanes, steam driven tanks, steam driven armored gypsy wagons, sailing, steam, and ironclad ships, etc., but that is not all that difficult for me. As a real world ex-Infantry Officer with a specialty in destroying armored vehicles, I am more than a little educated in how they are made and what can or cannot take them apart, or just as effective, kill the crew inside. As our family uses a heavily armed steam/sail ship for a primary home, I will adapt the large scale warfare rules, normally used on large troop contacts, to include armor, air, and naval engagements. Actually that will require a new set of rules, but it will be a variation of the previous ones. Again, as they say int the movie Matrix, when you learn to see things as lines of code, it isn't so difficult to re-write reality or to define it in terms of numbers.
The other major modification is that the weapon lists in the original game list only pre-gunpowder weapons, so the gunpowder era, modern weapons, and even futuristic weapons statistics would need to be added, but this is much simpler than most people, who don't write game or computer games would believe. All weapons are simply a description, a name, and a list of basic statistics amounting to range, rate of fire, damage, special effects, and special damage modifiers against various armor types. This is the same whether the weapon is ancient, modern, or futuristic. A few new armor types also need to be added, but attendance at any local Steampunk related convention makes it clear that ancient armor types still exist in Steampunk regalia extensively, albeit the armor statistics need to account for armor placed on limited body area without over complicating the combat system. I already have that arranged in the original game, well at least the modification of it I am currently using that is post publication, due to characters that already use better armor and/or chitinous armor from giant insects that they put only on a few parts of their bodies at times.
Yes we have giant bugs, scorpions, snakes, spiders, just like in the B-flick sci-fi movies of the past! where would early science fiction be without them? I especially enjoy the effects that even simple stink bugs can have macho warriors when the quantity of seemly gas ejected is increased commensurate with size on stink bugs that move from normal 1/2 inch size up to something 10 feet long.