iGEM
iGEM is a fantastic synthetic biology competition for undergrads and grad students. The competition has been running since 2004, and attracts teams from all over the world. iGEM is notable for the ambition of its entries, I think at least partially because undergrads aren't afraid to try wacky ideas.
The iGEM site is a great place to look for new ideas in synthetic biology. I found a long list of abstracts from each team, linked from http://igem.org/Previous_iGEM_Competitions. There are probably 100 startup ideas in here...
For example, here are the 2013 team abstracts: http://2013.igem.org/Jamboree/Team_Abstracts