Flagging a gadget slide show photo so it can be searched for later.

My daughter likes to apply long descriptive file names to her photos, not right after downloading, but rather when she sees an interesting one during a gadget slide show. I want her to be able to flag the changed photo so that I can later search for it, remove the flag, and update the photo on her external backup.

I tried having her insert a "$" somewhere in the file name, but Windows Explorer search can't find it, even if it's in position 1. It can find a tag, but there doesn't seem to be a way to tag a photo while it's showing during a gadget slide show.

Can you tell me what I (or the system) is doing wrong, and how I can accomplish this relatively simple task?

Thanks, but how is this any different from using "$ Nice sunset on the beach.jpg"?

I chose the $ because it was unusual and not in the list of forbidden file name characters. Maybe it should be.

I tried using an equally unusual "xxx" just before the .jpg, but search didn't find it. So I tried it your way, at the beginning of the file name and all was well. Not a very smart search. I know at least two languages with a single instruction that will find a sub-string anywhere within a string.

We're on our way. Another feather in your cap. Thanks for your help.