Guilty pleasures. Some say there's no such thing. I believe they're out there, though, those junk-food flicks ripe for enjoyment almost in spite of themselves; in fact, here's ten of the year's most shameless entertainments for your consideration, thematically paired.

1. 'Piranha 3D' and 2. 'Jackass 3D' -- Sure enough, 2010 was the year where game-changing technology backfired on us, first as vicious fishes devoured porn stars and then as Johnny Knoxville's band of hooligans let loose with all the full frontal floppiness that audiences could stand. If neither was worth the surcharge, then I'm not sure what is.