Here's my list. Some of the movies were so horrendous I can't believe I actually didn't walk out of the theatre or turn off the T.V. (When I watched them at home.)
Enough
Showgirls
Gigli
Glitter
Crossroads
From Justin to Kelly
Kazaam
Spice World
The list goes on and on...
edit: BTW, my girlfriend made me watch some of these.