The first massively (well up to 500 players) multiplayer game I played. I was due for a knee operation the next day and I wanted to stay up all night, I logged on my old 2400 modem on my 386 and played batmud all night. My 386 lasted a lot longer than it would have normally, thanks to this game. This mud is based origionally on the LP mud but has been drastically modified and enhanced. Complex guild, skill and combat systems, with a VERY large game world. The web site claims that it is the oldest LP mud, and I think this is very likely considering the complexity and volume of modifications. With a loyal following of players, a social and economic community prosered in my first virtual online experience. The text model for a mud allows a huge amount of creativity for the host of wizards developing new game enviroments. Having programmed a little in the lp mud programming language lpc, I can understand how such a rich world can be developed by a few commited mud wizards. Batmud is supported by player donnations and runs on it's own server at www.bat.org.
The first true 3D game that I played, immersive, consistant storyline and set in the Starwars universe. Simple flight model, no real space simulation here, but a lot of fun and not trivial to master. A good mission system created the need for some tactical planning to complete goals. Personally I think this is the best of the X-Wing/Tie Fighter/X-Wing vs Tie Fighter lot, I liked being the good guys. Seems like lucasarts have got back on track with X-Wing alliance, another fun game.
I basically missed the boat with this game, when it was breaking ground in the fledgling computer game industry in 1985, I was playing Sierra adventure games. I got into this incredible 3d space trading sim in 94 when the souped up Frontier Elite version was released for PC. This game used seeded randomly generated star system configurations to create the illusion of an infinitely large universe. The basic premise of trading to create wealth and gain starship improvements was extremely addictive. This game managed to avoid the tedium created by repetitive tasks to gain wealth and levels, by hosting the game in a essentially limitless universe. The vastness of the playing environment provided a diverse range of trading and combat opportunities that truly immersed the player.
Floateys Champion's Campaign
This first and best pen and paper roleplaying game I have played. It is amazing how good a game can be when the designer (in this case the gm) is not limited by technical considerations. Complex storylines driven by multiple factional forces and powerful characters. The champions system provides a generic character creation model that does not the limit the player in any way.
Vampire Collectable Card Game
Having some kind of mutant collector gene makes me a sad target for evil card producing mega-corperations sucking me of my meagre finances. Before they brought out umptine-billion (err ... apprently there were three) expansions this game totally rocked and I spent a hell of a lot of time hanging with my best buddies , drinking beer, eating pizza and playing vampire. Really tight combat system with lots of options and good balance kept us coming back for more. There were no "This card will let me win , yay , but it cost me 400 bucks" cards which is nice. I was never mugged by a horde of 15 year old, card mafia nerds in black leather jackets, carrying automatic weapons. So all in all a pretty good collectable card game.