xkcd#1190: Time viewer; featuring panorama and drag mode.
This is best viewed in as large of a viewing area (i.e. full screen) as possible. Currently featuring the official panorama 2015, 2066, 2349, 2552, 2681, 2743, & 2760. It is limited to these only, so far, but will be expanded throughout time to feature more panoramas. Playback of all frames (except the secondary frames) is supported. A GUI is being added, as well as other extras. Works in Firefox. Not tested in Chrome or mobile (touch) yet.
Changelog and files available at GitHub.