Being amused with spherical tag-cloud I wanted to try to create similar myself.

I tried... Then tried to improve it... Then tried to solve some compatibility problems... Now it looks like this:

I tried to avoid usage of unusual extensions, plugins and frameworks, so there are only spans flying around containing div.

However now I need some advices or suggestions on improving it's usability - both for user and developer. Any help or pointing out undiscovered problems of my approach would be greatly appreciated.