http://www.ncmo.org 
It seems to be a uniquely mormon idea, since once dating starts, pressure to marry starts. these guys set this site up to hook people up for an hour or two of non-committal make-out (NCMO), no strings attached. Google it, there's probably more info out there. My sister is mormon, she told me about it and I couldn't stop laughing for 5 minutes.
http://www.ncmo.org/new_policy.html under pressure of the LDS powers that be, they changed their site objectives