I've been testing G+ for a little while and i find the friends drag and drop into circle thing has a verry good effect (don't you think ?)
I was wondering how to achieve a similar effect when drag & dropping user into a circle using jQuery. It may give me a starting point in order to achieve this for a tree or a square. :)
Thanks
An opensource example of this is Circle Hack or Facebook Circles, source: https://github.com/voloko/facebook-circles Which could be customized for your needs (unsure about licensing though) It uses UKI.
If you want to achieve the same effect using jQuery I recommend using jQuery UI