In no particular Order:
Battletech Series-
Awesome series. I count this as one game because Mechwarrior 3 and 4 and Mechcommander 2 tie in my book. Mechwarrior 3 and 4 both offer graet graphics, excellent gameplay, and really fun multiplay (minus the lag). Mechcommander 2 has an excellent Single-player campaign, great graphics, and plently of HUGE user-made campaigns (some over 100 mb with cinematics. Yes, cinematics.)
Earth 2150:The Moon Project-
3-D Real Time Startegy with, *gasp*, actual strategy involved. Not the click fest CnC and Starcraft are, but still wickedly fun. 3 Very Distinct factions as well.
Descent II-
This is the first Descent game I've played and is the best IMHO. Lengthy single-player campaign, refined multiplayer code, and tons of user-made levels to download. On top of this is excellent music (the CD tracks, not the MIDI crap) and the wonderful Descent gameplay. Descent 3 comes close though.
(NOTE: This game and starcraft are the 2 games that really got me into gaming).
System Shock 2-
Play it with the lights off, at 12:00 at night, with the contrast up, either wearing headphones or using 4/5.1 speakers on EAX, with clean underwear. You'll see what I mean when I say some games are scarrier than movies.
Chrono Trigger-
Oldie but godie. Really, really good RPG from square. I compare all console-style RPGs to this game. None have matched it, although Final Fantasy 7 comes very close.
Runners up:
Half-Life-Probably the best single player game I've ever played. As for the 5 bazilion multiplayer mods, many are genious. Like Counterstrike, Day of Defeat, TFC, WormsHL, and others.
Homeworld- True 3D RTS, with great gameplay. Definately a great game. Can't wait for HW2.
Worms Armageddon- The funniest game I've ever played. Invite some sadistic friends over, play in hotseat mode, and watch hillarity ensue.
Red Alert 2- So it's not original. So it's not a Game-of-the-Year. So what? It's a blast to play, especially with a bunch of friends and mods. I do NOT like the crappy copy-protection though. Makes LAN play quite difficult as you have to find a keygen to do practically anything with over a LAN with 1 set of CDs.
Descent 3- Great game with excellent multiplayer. The single player leaves alot to be desired though (although a few missions are really good). Agian, great user-made mines and mods, thanks to the ever-great Descent community.
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