A question regarding the Slice tool.

Hello to all, I come bearing a question. I'm an icon and texture/resources maker, and as most of you know, cropping becomes an essential part of my work. Sometimes, especially with large textures that I want to break down into smaller pieces, I need different parts of the base (whether it be a large texture or a screencap) to display in different file windows, and going through and cropping the original fifty times would be an extremely tedious process. I remember reading a post a long while back about the Slice tool and how it can help me do this, but I've only gotten as far as marking the original picture with tons of slices and forgotten how to actually divide them into individual files. If anyone could help me with this, I would be eternally grateful :) By the by, I use PS7.