You might find it interesting that a fellow HN-er (read: me) totally geeked out to this in college.
I even built a better version of the game engine which is still actively used at Mizzou and Truman State: https://github.com/mikeknoop/knoopvszombies
I even built a better version of the game engine which is still actively used at Mizzou and Truman State: https://github.com/mikeknoop/knoopvszombies
Also, now I've got an urge to submit a patch allowing sub-fora for squads and factions. I can't believe it only hit me yesterday what fun it would be to wreak politics on a game of HvZ!