[EricH]

You could make your own actuator, in a sense. It's a matter of linkages, though, and a slow-enough motor. I know a typical window motor can slap through 120 degrees in a second or less... but if you were to use a linkage on an arm off of that you could slow that way down.

Actually, this is where a speed controller can come in really handy. You can take a lot of the speed out in the speed controller if you want to, meaning a smaller (or no) gearbox.