cantango extension for cancan
Kristian Mandrup has released cantango.
It's a layer on top of CanCan that integrates nicely with Devise and other authentication systems. It supports caching of rules, subdivision of abilities, and supports storing and loading the abilities from a store. There is also built-in support for a fall-back Guest user and/or Guest account. It is very easy to integrate with any roles solution, including troles.