RSVP is a solution along the same lines of evite! or Yahoo! invites. You can use it to create a Web invitation that is mailed to each one of your guests as the guest account is created.
Open source project that offer summary and download services on this page is a project that carry out their development work on other open source development sites. Their work is linked to this page via a feature called OFI, and their work is not carried out here on OSDN site.