Here is a bug I found when I was respeccing, and wanted to test out the dps it could do when farming in uldaman, I dont know if I'm the first one to show this but here you go. It's very short and no editing at all.

If you pop rampage outside of the instance and stack it to 5 and then enter, the charges will reset to 1 and you can stack 5 more upon the 5 already active, do this a couple of times and you will stack over 30k AP.

*note* This is not on a private server and could be used to expoit boss kills very easy... don't :P.