Active Desktop! Didn't you just love that thing? ~
Kind of. KDE seems to be about the only place where that kind of functionality lives on.
Was an amazing demo, but a security nightmare. Shudder.
And ActiveMovie, which became DirectShow. (which I only remember since Apple lampooned it by internally naming a window used by QuickTime "InactiveMovie")
Examples:
* Active Server Pages
* ActiveScript
* ActiveX