Arena Drinking Exploit
As it should work: When a pet attacks a drinking player, that player is forced to stand up after being put into combat, thus stopping the drinking.
The exploit: If the water drinking character spams a /sit macro repeatedly while being attacked by a pet even though they will be put into combat they continue to drink because the /sit macro overwrites the default /stand behavior that is supposed to occur once they are put in combat.
What this means is in any arena where the healer can get out of combat long enough to start to drink (easy for druid healers) they can begin their drinking and finish it all the way even if a pet is attacking them.
So it stands with the obvious exploit, getting out of combat to drink pretty much guarantees you a full helping of mana regen. Not a bad deal, but the flipside is that if you get hit with melee attacks while spamming the /sit macro, you'll be getting crit with each passing blow. Ouch. So use with caution.
Hit the Elitist Jerks Forums for much more goodness. Enjoy. =)