I take far too many photographs! I have freely licensed over 9,000 of them – you can find them on Wikimedia Commons at Category:Photos by Mike Peel.
Timelapse photography is where you take the same photograph repeatedly at a set interval (say, every 5 seconds), and then the resulting photographs are turned into a video. This lets you speed up the movement of something, so what might have been unseen as it happens so slowly becomes very noticeable.
The timelapses here are all available under the Creative Commons Attribution 3.0 license.
Jodrell Bank Observatory
As I work at Jodrell Bank Observatory, the telescopes are the obvious things to make timelapses of.