ANSI animation
Moving ANSI art in which escape sequences reposition the cursor and redraw parts of the screen, with the modem's speed serving as the frame rate.
Ordinary ANSI art draws top to bottom and then sits still. An ANSI animation — usually called an ansimation — uses the same cursor control that ANSI.SYS understood to jump back and overwrite characters, so a logo slides in, text flashes up or a figure moves. The format had no notion of timing; the pace was set entirely by how fast characters arrived over the line.
That had a charming side effect: an animation made for a 2400-baud modem was over before you could see it when displayed locally or over a faster link. Viewers ended up pretending to be slow modems. The form lived on login screens and in BBStros, and was often drawn in TheDraw.