M1 Finance dropped their fees to zero yesterday!
Which I think is fantastic since I had decided to use them a few months ago (because of their unique portfolio model which allows you to build a custom one).
So, AFAIK, there are now two free robo advisors: M1 Finance and Wisebanyan. I've tried them both out, so if anyone has any questions I could probably answer.
(Three if you count Schwab Intelligent Advisor, but their minimums are much higher.)