I like changing my stylesheet too frequently, so I set up a read-only (read & write for admin) forum that I posted the name of the stylesheet as the subject, then screenshots of what it looks like as well. A couple stylesheets we used uncommon fonts, so I was able to attach the font to the post if people wanted to download it. You can see the forum
here. I still haven't gotten around to doing even 1/2 of the ones I have installed.
I know this isn't exactly what you wanted, but it may be a temporary fix until someone writes the hack.
