Our D&D group wants to do some Reign-style company action, where the PC group gets to act on the larger, group-size scale of the setting. We talked about maybe just using Reign's system as is, but I wanted something different.
So, here it is: A system for group-level actions in D&D 4e
Check out the 1-page PDF and let me know what you think. The basic idea is that your group is created like a character, and it can fight other groups on the "group battle board." You give your group actions by completing encounters at the PC-scale (much like you do in Burning Empires).
So, the Company of the Raven raids a goblin cult of Orcus, and you play out that encounter with the PCs. Then, based on what happened in the encounter, the players get to do a "group move" on the group battle board, and attack the Orcus Cult enemy group, or go defensive and grab some "cover," or acquire a better group-level weapon, or whatever. The group-scale character can level up and get new abilities and stuff, too.
The GM might want to make a custom group battle board with interesting terrain to represent the nature of the conflict between the groups (like zones that give attack bonuses because of attracting followers or whatever).