I think any Gif will do that
if it's optimised beyond a certain point. The best is with transparent backgrounds. You get almost a time lapse effect.
(
Artamnesia,
Wed 5 Mar 2003, 1:13,
archived)
Is a good by-product
just never had a use for it as yet :)
(
Chromatically Challenged,
Wed 5 Mar 2003, 1:15,
archived)