Just wanted to share a new approach I'm trying for my own side project. (qiip.me is a personal site generator)
To try it out, just use the URL. For example:
http://qiip.me/try/github/mdo
This would fetch a github account and enable me to try different themes. You could also do:
http://qiip.me/try/github/ed-lea/dribbble/edlea
Check out the home page qiip.me for other services supported.