There is, what appears to be a Cyanogen Mod “CM6″ leaked rom for the Nexus One.
I was googling for information and kinda stumbled across it. I’m not going to link it, because it’s very much a dev build, and you don’t honestly want it anyway. It has no gapps, etc. It’s not at all a usable rom for the average person, I just thought I would post it for shits and giggles.
It lives! Now go donate so they feel obligated to finish it faster 
Note – If anyone involved in CM6 wants me to take this down, email me, and I will.