Since the link to McGill's tool is dead -and I was too lazy to search for a different one - I whipped this up myself.
This little tool should help to keep your servervault clean. You can specify how many days a character must have been inactive in order to get affected. All the characters can either be moved to a separate folder or deleted.
Written in Visual Basic, so it's windows only.
I also have no idea if it needs any .net framework or whatever. It ran fine on the only other machine I tested it on which didn't have visual studio installed.