This came up because of Jason Scott’s posting hundreds of “Under Construction” animated gifs (warning! that can crash your browser!), derived from Archiveteam’s attempt to backup Geocities before it closes.

Seeing that page led twoleftfeet on Metafilter to reminisce about creating the first “Under Construction” animated gifs, mentioning the earlier, clunkier “server push animations.”

A thread on Hacker News centered on that story. Scriptor asked “server push animations? How were those done?” And I dug up some information – including an implementation – & posted it there.

I’ve been curious about what it would do on current browsers, so. I took the Perl script, hit the Internet Archive’s Wayback Machine for some canonical test images, & put them together to make:

This is a server push animation. It surprised me that it worked in Firefox & Mobile Safari.

I can’t say that this is terribly useful, except for historical interest. Each frame of animation is sent as a separate picture, so, for example, a loop would require an ongoing connection.