It's a pretty awesome stealth game! Its out for PS2, Gamecube and PSP.
It has a great story line too. It is almost like a movie!
http://en.wikipedia.org/wiki/Metal_Gear_(series)
EDIT: If you want, you can view the entire game here:
http://www.youtube.com/watch?v=7gNfQkO7bmA&feature=PlayList&p=BA7BB2A22C46B15C&index=0&playnext=1