Man what a great game even after all these years.
Agreed! I only really played and beat the 32X version (and tinkered with the PS version), so I'm finally seeing what I was missing. I breezed through Ep one on Ultra Violent, but had to take it down a notch when I started Ep two as the "ass handing" began in earnest!
Half-Life 2 - Entanglement level
Team Fortress 2
Gyruss - loved it as a kid
Kind of in queue:
Beautiful Katamari - really want to go back and finish out achievements (currently at 800/1250)
Halo 2 - was on the home stretch when I switched to HL2.
I just picked up a Soul Caliber IV Hori Stick so I'm hoping to get a little better at some XBLA games and Virtua Fighter V.