If you've been using Instagram, the popular filter-based photo capturing and sharing app for iOS, you're probably aware of its lack of a decent web interface. Webstagram provides exactly that.
You log in to Webstagram by logging into your Instagram account, so no need to sign up for anything new. Once you do it provides you with your photo stream and various statistics (for instance, I was surprised to find out I have more than zero followers).
But it's not just your photos—you can view any photos posted to the Instagram service, browse by filter, search for a specific user or tag, and much more. Basically, it does everything you'd expect to see on a photo sharing service and has been missing from Instagram since it was released.