An interesting experiment is that if you have FB on your smartphone, you can use the "Find Friends" feature to dig up all sorts of profiles for the contacts on

An interesting experiment is that if you have FB on your smartphone, you can use the "Find Friends" feature to dig up all sorts of profiles for the contacts on your phone. I think it uses a combination of phone #'s and email addys from GMail...? Among others, I've found: * several FOSS devs that I've emailed * a few people that I've had brief business dealings with years ago * my landlord * several that I recognize as wrong #'s from the past (such as the girl who texted me 10+ times even though I told her she had the wrong #) * some old co-workers from 5+ years ago (I have some old emails from them) * quite a few that I don't even recognize They quite literally will trawl every piece of possibly-relevant data on your device.