As some of you may know of the northern exposure achievement. It is the one where you have to kill a rare mob in Northrend. Well my friend got the achievement without even killing a rare mob. What you need to do is be in a group with someone who can kill a rare mob. If they kill it and you are grouped with them then you still get the achievement even if you are in another zone.
I learned about it when both my friends got the achievement just for being grouped. My friend was in Icecrown killing the rare mob while the other was in Sholazar Basin. Below is a screenshot showing them both getting the achievement. So basically if you see a rare mob, invite some guildies and get them the achievement too. Some testing would be great since I have only seen this happen once.
Screenshot of achievement: nE.jpg - Image - Photobucket - Video and Image Hosting