From Tersus Software:
To coordinate a meeting, you specify a list of participants and one or more possible times (and places). When you press 'Create Event' an email invitation is sent to each participant. Each invitation mail contains a link that the participant can click to "vote" for a preferred selection of time and place. The responses of the participants are saved, and you can always view them by visiting the meetings "Dashboard". Once you select the meeting's final time and place, you can use the application to automatically send calendar invitations to all participants.