Hi Max, a particle system will do that sort of thing. To quote Kevin Camp in another post:
create a new solid and add cc particle world. in the particle settings, set the particle type to textured square, and then in the texture settings select your GIF as the texture layer and set the texture time to birth. a little lower in the particle settings, set the birth and death color to white (this will prevent particle world from tinting your images).
There are quite a lot of tutorials about CC Particle World which could give you the basics.