Here's the few that ended up stuck in my head immediatly after hearing them.
You want a piece of me, boy? Starcraft Terran theme
Outstanding Starcraft 2 Terran theme
They're in the vents! Space Hulk Title theme
Wer ya want da dakka dakka? DoW2 Great Devourer (Tyranid name but played for the Orks? Looted as ork theme)
This game has some great music Crash Bandicoot 2 Jet pack level theme
And one of the few sewer levels that didn't blow Crash Bandicoot 2 Sewer theme
I almost feel bad for the orcs... Almost Orcs Must Die! Set up
That looked like it hurt Orcs Must Die! Battle
Follow the Freeman Half-Life 2 What Kind of Hospital is This?
This one's for you Dark Quake 2 Crashed Up Again
Well! Wot cannai doo for ya? Diablo Tristram Theme
And now to complete the trio Warcraft 2 Orc Theme
I WILL EAT YOUR RIBS Team Fortress 2 Rocket Jump Waltz
ROBOTS! Team Fortress 2 ROBOTS!
I have nothing witty for this Age of Empires
Atlantians were bullshit but Egyptians were just as bad Age of Mythology The Ballad of Ace Lebaron
Now you're on MY time you little SKUNK! Crash Bandicoot Warped Dr. N. Tropy Theme
Fairly menacing final boss theme Crash Bandicoot Dr. Neo Cortex Theme
FINAL JUSTICE Marvel Super Heroes Captain America Stage
Oddly enough, I don't think HULK SMASH is used for any of his move names in this one Marvel Super Heroes Hulk Stage
WASTE OF FLESH Marvel Super Heroes Shuma-Gorath Stage
We die standingDawn Of War: Winter Assault Imperial Guard Theme
I still love this course Crash Team Racing N. Gin Labs
Not the entire song skip to about 2:15 WoW Mists of Pandaria Shado Pan Monastery
Cata gave some pretty great stuff WoW Cataclysm Burning Steppes
Some more WoW WoW Cataclysm Winterspring
Storm Peaks was my favortie part of WotLK WoW Wrath of the Lich King Storm Peaks