Syzygy23 said:
Hmmm, other than Gamma World, the closest to a post-apoc TTRPG that I know of would be Unhallowed Metropolis:
http://tvtropes.org/pmwiki/pmwiki.php/TabletopGame/UnhallowedMetropolis?from=Main.UnhallowedMetropolis
http://tvtropes.org/pmwiki/pmwiki.php/TabletopGame/UnhallowedMetropolis?from=Main.UnhallowedMetropolis
I've GM'd a few sessions of it and it's pretty damn good, combat is fast and brutal, and God help you if you go outside the city walls without a cartload of ammo.
The style is less "modern" and more "Steampunk" what with the whole Neo-Victorian themes and Tesla weapons (Ball lightning generators on the city walls, anyone?) But it hits all the criteria for a post apocalypse themed game (Mass zombie uprising in 1905 devastates an unprepared world, strange blight starts spreading killing off fertile land slowly, the last bastions are overpopulated, ridiculously polluted walled cities by the year 2105, and everyone is being beset by raiders, deviants, mad scientists, zombies, vampires, cults that worship Jack the Ripper, and strange Mr. Hyde type people called Thropes. Also, everyone and their mother has a gun that shoots lightning, have fun.)
Now now your setting info is a bit wrong, galvanic weapons aren't really in everyone's hands, though the setting is about the most grimdark I know. It's not even ott dark humor grim dark, it's just humaity is almost doomed to a slow death as is the world. Though yes it's a game world where the trains are small tanks with huge plows and while the wastelands are naigatorable on foot you do not want to go near an abandoned city and even then you don't want to drop your gaurd.
As for other PnP games, there's Exodus http://en.wikipedia.org/wiki/Exodus_(role-playing_game) was orgionally going to be an offical Fallout PnP but the licence got pulled so they filed off the serial numbers so to speak.
Looking over my PDF collection I have a few PA PRGs I haven't really looked at such as:
Earth AD.2- Earth is now a wasteland sunded by mans many failures (only looked at in passing)
EABA- a muliti setting RPG system has PA settings
GURPS- same as above
Apocalypse World- Only seen in passing seems an intresting PA RPG though.
Atomic Highway- "standard" PA RPG (not looked in to much of it)
RADZ- an PA game that looks to by fast, cinamatic and wild. (not really looked in to it though)
Remnants- a PA mecha RPG. The mecha being remnants of a former age.
I'm sure I've missed a few but that's my RPG collection for you.