Here's the answer.....
I have a Sony DCR-PC101 mini-dv camcorder. I was using ichat with my friend, and sure enough, it would turn off after a set amount of time.
My camcorder can act like a digital camera, taking 1mp still photos. If i set it to photo mode, it will never turn off. The reason is, that the camera thinks you're constantly about to take a photo, so it's always focusing, read to shoot.
If you put it to camcorder mode, it turns off after xx:xx time, to save battery.
Also, don't forget to plug in the ac adapter, and take out the battery....you'll never run out of juice! :->
This ofcourse works, if you can switch between digital still camera, and camcorder.
No tape required to be inside....