Form factor for a large LED array on a small board
I'm using a Micrel MM5450... still having some small problems with it but bound to have it working on the next few days. It takes only 3 connections to your microcontroller (clock, data enable and data) using serial comm. and it can drive up to 34 LEDs.

http://www.youtube.com/watch?v=Shg0nCd6DRk