VBulletin is awesome forum software, I'm on several forums that use it, but it's more complicated to administer (and more secure, as a result), and it costs money. PunBB is open source. Beemaster uses SimpleMachines, which is free, but if you want to support them they offer a subscription for $49.95 a year (which isn't too bad). I agree PunBB isn't quite as easy to use as the others, but it's a far sight better than EZBoard, which I've never been able to stand. I think if I were to run a forum I'd start with SimpleMachines, but that's just me