Advowire - Advowire is a great crowdsourcing software for social media influencers!

FameBit - Easiest Way to Find, Hire, and Work with YouTube Influencers

Influenster - Influenster is your source for honest product reviews. Discover new products, read beauty news, watch tutorials, and shop and share your favorite products.

Assmb.ly - Powered by intelligent technology, we’re delivering the content readers need, exactly when they need it, across four dynamic brands (and counting).

Pollseye - < 30 seconds video reviews of products ("user-generated QVC")

inzpire.me - An end-to-end solution for influencer marketing