I'm always privy to simple, one-shot tools that get the job done. ScheduleOnce is a good example of a meeting scheduling tool that's been designed with this in mind. The free service is set up to help you reach a consensus on a meeting time for multiple parties based on open time slots. Each user has access to a calendar, and depending on how open the meeting's creator has left the schedule, users can go in and note times they're free, or accept any slot that's already been noted as open. The app takes time zones, including various localized daylight saving times, and adjusts the schedule accordingly. That combined with the iCal and Google Calendar-like drag-and-drop time slot creator makes it supereasy for people to jump in, mark down a time, and be done with it.
The real draw to this app is its simplicity. There's no sign-up or registration required, and when it comes time to figure out what times are best, the app will designate each time slot with different symbols to give you a quick look at which times are free, which aren't, and a few that might be negotiable. You can also view this in a large calendar view in case you need to haggle with a single member who's flubbing up the operation. When it actually comes time to decide on something, you can either cut and paste the provided text into an e-mail, or do it right from the page. It's even nice enough to break down what times the meeting is at in each participant's time zone.
In addition to its general purpose app, ScheduleOnce has a private, white-label edition that companies can use inside their firewall, or mix in with pre-existing conferencing and meeting systems the likes of MeetMeNow and GoToMeeting. Ideally, I'd also like to see some integration with calendaring apps such as Outlook and Google Calendar to let people share a portion of their schedule without having to fill in any time slots, or plug the date right into their calendaring app of choice when a time has been chosen.
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