[quote name='Tsukento']Here's a list of games worth getting that came out in the US. I'll leave the imports up to others to bring up.
[/QUOTE]
I'm going to add a few more that I feel are worth owning:
Alien Front Online (Tank battles is small arenas... was great fun online, but is till pretty fun in campaign mode.)
Bleem (+ Metal Gear Solid, Gran Turismo 2, and Tekken 3. You probably own all of these games, so why not play them at their absolute best? Seriously, it puts the PS2/3's graphical polish on PS1 games to shame.)
D2 (Set in the Canadian wilderness, D2 is survival horror at its most... insane? It's by Kenji Eno, who is well known for his company WARP's ability to make really strange and unique games.)
Dynamite Cop! (The Dreamcast is an arcade machine, so why not play one of the most fun arcade ports for it? It's not the deepest of game, but it's a good example of stupid arcade fun from the late 90s.)
Grand Theft Auto 2 (Probably the best version of this classic game... but make sure to play it using a VGA connection.)
Illbleed (The most innovative survival horror game since Silent Hill, you take on the role of a girl who is attempting to survive a trap and horror filled amusement park for a chance to win big money.)
Maken X (The only Atlus game released for Dreamcast... if you like Atlus [Shin Megami Tensei games], this is for you... super weird and violent.)
Metropolis Street Racer (Consider this Project Gotham Racing 0, because it is.)
Outtrigger (Why play Q3A or UT on the Dreamcast when you can play a FPS specifically designed for the console... grab this before you grab the ports.)
Record of the Lodoss War (Anime + Diablo 2... one of the most addicting and long lasting games for the system.)
Red Dog (Vehicular combat with fantastic multiplayer.)
Re-volt (RC-Car racing... If you like Toy Commander, you'll probably like this, too.)
Silver (If you prefer more... "western" RPG fare.)
Sword of the Berserk: Guts' Rage (Based on the anime Berserk, it's really, really violent... splays kind of like the Dynasty Warriors games mixed with Devil May Cry.)
Tokyo Xtreme Racer (I like Need For Speed: Underground better, but this game allows you to race on actual Japanese highways... that's gotta be worth something, right?)
Virtual-On: Oratorio Tangram (A lot of people will tell you that this game sucks, and it does if you don't have the right equipment. Get some twin-sticks, and it's amazing.)
Virtua Striker 2 (The only soccer game I have ever enjoyed. When you make a goal, the ball leaves behind a rainbow trail! Those crazy Japanese...)
Zombie Revenge (see: Dynamite Cop! + zombies.)