So back in the early 2000s your "homepage" might be on someplace like geocities, and you'd be able to add a bit of HTML like this:

<A HREF="http://www.some-place/a-sprite.html"><IMG SRC="http://www.some-place/a-sprite.gif"></A>

It's a link to an image on another server, and adding that HTML would add that image to your homepage. The idea is that it'd be a picture of a cartoon character saying something and it might give you a different message next time you looked at your homepage because they'd periodically change the image on their server.

Anyway instead of a cutesy cartoon character saying positive uplifting things, some wiseguy made a cartoon character called "Tina the Troubled Teen". "She's fourteen, listens to Switchblade Symphony, cuts Geography class, and smokes cloves when no adults are around." according to the creators Lore Sjöberg (who is on mastodon, btw! I should DM him soon as I figure out how to DM on mastodon...) and Lori Matsumoto.

For some reason I remembered this in the middle of a discussion about Goth bands recently and I spent half an hour looking this up.