I'd love to have CCleaner on a thumb drive and be able to select which drive I want to clean. Unless I'm missing something, you have to have CCleaner on any drive you want to have cleaned. There could be a 'default' drive to clean but perhaps in options, of "Select Drive".
Great idea. I have another program "Eraser" that wipes my 'free space' but I would much rather use CCleaner. Adding 'wipe free space' - maybe as a scheduled activity (hint, hint) would be totally awesome.