We've had this a couple of times before but theres a few new posters so this thread again cant hurt.
Mine:
Vagrant Story (and anything else by Hitoshi Sakamoto)
Killer 7 (and anything else by Masafumi Takada and Jun Fukuda, God Hand
)
Baten Kaitos, Baten Kaitos Origins (and anything else by Motoi Sakaruba, I think he did the soundtrack for Eternal Sonata, I'll have to pick that up when I get my 360)
Etrian Odyssey (and anything else by Yuzo Koshiro)
FFVII, VIII, IX
Wip3out (popular progressive trance DJ/Producer 'Sasha' was contracted to compile the soundtrack and write a few original tracks just for the game)
Castlevania: Portrait of Ruin (I would say SotN but everyone says that, Portrait is by Michiru Yamane also with help from Yuzo Koshiro)
Devil May Cry 3
Sonic R
Batman and Robin for Mega Drive/ Genesis (and most other stuff by Jesper Kyd)