To extend on ddm999's post, I was trying to find out which other Source mods have been released so far. First mod collection I found:
http://steamcommunity.com/sharedfile...s/?id=94164282
Released Source engine games (commercial)
Aperture Tag (Portal 2)
CONSORTIUM (Kickstarter)
The Stanley Parable (previously a mod)
Released (Gold)Source mods (free)
Cry of Fear (HL1)
Estranged: Act I SDK 2013
Fistful of Frags Source Engine 2013
Half-Life: Before (HL1)
NEOTOKYO° SDK 2006
No More Room in Hell SDK base 2013
Thinking with Time Machine (Portal 2)
Unreleased, but shop page exists
Conversion (Portal 2, free, Greenlight page has been removed)