Bourne Identity
300
Casino Royale
Fantastic 4
House on Haunted Hill (i prefer the one with just Mike)
Independence Day
Halloween 3, Frogs (iriffs by Hor-riff-ic)
Minority Report, League of Extraordinary Gentlemen, Speed, Die Hard (iriffs by RiffRaffTheater)
Jaws
Next
Memento
Matrix 1&2 (the third is just ok IMO)
Over the Top
Plan 9 from outer space and Reefer Madness (either the one with just Mike or all 3)
All 3 Spidermans
X-Men 2
Swing Parade
X-Files
Both Star Trek New Voyages (World Enough and Time, and To Serve all my Days)
Those + what Ross mentioned are ones I can watch over and over and are all pretty damn good.