My experience with http://builditwith.me has been very poor: a handful of contacts in 3+ years, almost all "ideas" people seeking designers/ developers to build their app for free or paltry sweat equity.

There's also no way to remove your account or update it to reflect you're no longer available or interested in collaborating. I've emailed Drew numerous times asking to de-activate or de-register my profile but I've yet to receive a response.