Idea Banks

Creativity Pool
A global pool of innovation and new ideas. People can browse the database and search for creative inspiration, or donate their unused creativity and be rewarded.
http://www.creativitypool.com

Global Ideas Bank
An International Suggestion Box for socially innovative non-technological ideas and projects, with £1,000 UK sterling awards annually for the best ideas or projects submitted.
http://www.globalideasbank.org/

Halfbakery
A communal database of original, fictitious inventions, edited by its users and spanning many topics.
http://www.halfbakery.com

Idea A Day
A new idea every day.
http://www.idea-a-day.com/