As I, Jamie Tanna, have had great benefits from creating an iCalendar feed for my RSVPs, I thought I'd make this a service that anyone else can use, too.
Point the below form to the feed URL that produces a set of Microformats2 marked up RSVPs.
You can either click Submit to browse to the URL, or the text box below the form will produce the URL to point your calendar application to.
Want an example? Check out what my site's RSVPs look like.
Note that it can take up to an hour to sync a calendar. If your calendar is not syncing, please raise an issue on the repo.