Hey, I noticed that Lorde created a Perl script for naming files, but in my messing around I figured out that if you shift or ctrl select multiple files, then right click on them and rename it will add a (#) to the end, so if you say select all of your sex pics for a character and do it, they will all be numbered differently.
Sorry for the punctuation but I thought this might be a useful trick, although I am not sure if it is specific to windows 7 or not