It was a shame to see this system and this company go belly-up. Action! (Mustn't forget the exclamation point!) was to the Hero Games rules (nee Champions rules) as Champions was to Superhero: 2044. That is to say, a huge leap forward, and quicker to deal with.
Very adaptable, very useful, and - during its time - very well supported. Thank goodness that its supplements and adventures are still carried here as PDFs.
There's even a free PDF which includes almost every rule. But download the Full Version, throw a couple of bucks. The interactive links alone are worth it.
[5 of 5 Stars!]