i recently discovered, after visiting a fan site for Equilibrium, that there is something called an animated gif. Coolness! A picture file that animates! Putting one of those on a website would make the site so much cooler.
I found out that mplayer can output animated gifs from video files using -vo option. I need to investigate further to find out how to control resolution of output and how to restrict the time mplayer plays. This will be rather more complicated.