I believe Clickpass was YC '07. Falling short of a Series A raise, Yola/Synthasite acquired them in 2008 [1]

Then a few years later (2012), Yola sold the IP and users to Janrain [2]

[1] https://news.ycombinator.com/item?id=402973

[2] http://janrain.com/clickpass-acquired-by-janrain/

EDIT: my pleasure callahad :)