I really like the Mac Rumors forum application. I know they use Vbulletin and that this probably what I will use on my site but, 1. I know there are a lot of great Open Source Forum Software Applications out there. Please list all the ones that you know about and recommend. Hopefully something that is as good if not better than vbulletin. Does not matter if they are not open source still list them please. Thanks in Advance.