incremental file names

I need to create a zoom in a slide show that does not have a zoom effect and have used an action to create a new layer, scale to 101 percent and then save the file. I will run the action as many times as needed for the amount of zoom needed. I can’t figure out how to make Photoshop save incremental file names or number from an action. If someone knows of an alternative way to accomplish the zoom effect for a slide show, I would greatly appreciate it. Photoshop 7 or 8
Thanks,
George