A lot of sites offer email reminders, web-based to do lists, and even reminders via Twitter.ReminderFeed puts your reminders somewhere else, somewhere you're likely to see them: in your RSS reader. It's ideal for recurring reminders that you want to see in your reader periodically.
ReminderFeed is a good concept, but I'd like to see it develop more customization. Some calendar apps can already deliver your events as a feed, and ReminderFeed isn't going to keep up with those if it doesn't offer, for example, multiple events within the same feed.
Right now it's good for a daily mantra or routine, but it has the potential to be a middle ground between the simple service it offers now, and the overcomplicated featuresets of some calendar apps.
