Multiple exposure help

[sproutpunx]

Apart from taking lots of photos on a tripod, combining them as layers in photoshop and then removing parts of each layer to reveal the next exposure, is there any other way of getting the same object twice in a photo?

That sounds a bit confusing, basically the idea I want is to see an image move accross my photo using multiple exposures, and I was wondering if there was any way of maybe combining the photos where just the new parts are included?

If this makes no sense blame being stuck at home to revise for finals with no human contact all day!!!

 

[sproutpunx]

thats pretty much what i've been doing, was just wondering if there was some clever option in photoshop to add the two images so that it just contained the new information on the photo if that makes sense.