Hunk Money had something like 1,000 or 2,000 clips available for tubes when I looked ... it was an insane number for a single sponsor.
Intense Cash converts like crazy on tubes (I am currently at 1:198 on tube traffic).
Gunz Blazing has lots of tube content.
Buddy Profits has great vids available.
Pride Bucks has a ton of vids but you have to hit up the affiliate manager for FTP access to them -- real easy.