I know that the thread was supposed to be Dreamcast and prior, but all my backlog is post-Dreamcast. here it is, anyway, in no particular order other than alphabetical:

PS2:

Culdcept
Disgaea
Dynasty Warriors 3 & 4 (plus Xtreme Legends)
Fatal Frame II
Herdy Gerdy
Jak & Jak II
Magic Pengel
Manhunt
Warhammer 40K

Xbox:

Crimson Sea
Deus Ex: Invisible War
Prince of Persia: The Sands of Time

Cube:

Beyond Good & Evil
Metroid Prime
Viewtiful Joe

GBA:

Mario & Luigi
Sword of Mana
All 3 Castlevanias