TRIBE Group - TRIBE is a self-serve marketplace connecting social media influencers with leading brands to create social media campaigns.
Productbox - Talk with fellow product managers about how you do stuff.
Join - Join is a marketplace for influencers and advertisers to collaborate.
SnakeLogic - The puzzle based snake game
RankSider - RankSider connects brands with bloggers and Influencers.
Gumroad Small Product Lab - Bite-sized lessons to help you launch your product.