TOPIC: slightly off topic, but related

I'm looking for an extension to help determine the best date for an event by users entering their availability at several different times., such that when a defined number on any of the given dates is reached I can publish the event.
[url=http://scheduleonce.com:3v31wo91]ScheduleOnce[/url] works like this with google calendar.

(I was going to ask this at jevent's forum, but their login system is behaving badly and claims I don't exist, yet won't let me reregister because I'm already registered as a paid member )

I don't know of an extension designed to do this but perhaps you could use a survey extension. You could provide several windows of time from which they can vote. Allow them to choose multiple options. The extension would calculate (some would even "chart") the results and you could schedule your event for the day that does best.