The Universal Key
The Universal Key is a Horde-only quest for level 10-30 in Northern Stranglethorn. It rewards 1 reputation reward, 4,100 experience and money.
Description
We're going to need something even stronger than those beefy <race> hands of yours to open this. And the Venture Company schlubs to the northwest might have just the thing.
Last time I was over there, I saw shredders walking around with giant rotating blades on their hands. That's one way to open a box!
If you can't find any shredders, you might also try the giant sawblade in their lumber mill, by the lake.