Create and share video playlists from youtube without logging in: http://cueyoutube.com/

Easily create digests of emails using forwarding rules: http://emaildigest.me/

These two don't really do anything, they're just ideas with Wufoo forms:

Find out where you rank in terms of salary for your industry and location: http://pimpmysalary.com/

Get a Chinese Business Name for $500: http://www.chinesebusinessname.com/