fab.com (included in the list as once having a 1B valuation) was sold in a $15M fire sale [1], which does make one wonder..

[1] http://qz.com/300825/how-fab-com-went-from-a-1-billion-valua...

Everybody knows it's bullshit, but what else are you going to do quantitative studies on ? Number of Facebook likes ?

You can fudge it, probably 2-3x, with liquidation, but a $300mil actual valuation is nothing to sneeze at.