Favorite Video Game OST

Hello fellow Polynaughts,

I know we have a "Music" thread already, but I'm interested to know which game soundtrack you like the best. There are some wonderful OSTs out there and boy do I love listening to video game music while I'm not playing them. For me it doesn't get any better than Donkey Kong Country 2: Diddy's Kong Quest. That bizznizz is legit. How about everyone else?

Note: Sorry if this is already a thread...