Are you talking about motorized props? Since most of my props are run with windshield wiper motors, I run them off 12V batteries.
A lawn mower battery will run a wiper motor prop for about 20 hours before needing recharged.
I run a Monster-in-a-Box, pop ups, a grave grabber, and rocking tombstone. All props made with wiper motors. There are several sites with plans for projects. In my book, the best by far is: http://www.scary-terry.com/wipmtr/wipmtr.htm