Flare by GoDaddy - Discover, give feedback and support startup ideas
Founders Nation - Find or become a startup cofounder
Wittycircle - Networking tool for entrepreneurs, makers and curious minds.
CoFoundersLab - Meet 250,000+ entrepreneurs online
Generating Product Ideas - Find ideas for your next business or side project
Co-founder Question Cards - Questions to ask your co-founder to know each other better.