A recruiter sends a job offer to 416 developers, mistakingly putting each developer’s name in the To field of the email, instead of BCC. Boom, instant community, complete with name and logo:

It is such a fascinating thing to watch. It’s like a flash mob, except the surprise is on us, the mob participants. It’s like we were all beamed into the same virtual room by one single person who chose the group of us, and left us to figure out what to make of the situation.

The resulting list was named Pradipta’s Rolodex, after the recruiter.