The problem: organizing a group meeting/meal/activity. Figure out who has time when, who can attend, pick a time, etc.

Evite works, but is relentlessly commercial and spammy.

Via Life hacker, Renkoo and Diarised.

Haven’t used either yet, but keep meaning to. Nice use of web, methinks.

Update: 2/25/07: The COO (!) of Planyp.us suggests his/her site as well - see comments.