Hi guys. I'm getting kind of tired, so I'm going to just get into it right away.
1. Go to the Violet Citadel:
2. Go through the portal to the Purple Parlor, run outside, mount up and fly over to where I am in this screenshot:
3. Dismount (this will kill you), then do this exploit as a ghost:
New way under Dalaran
4. Once you're under, resurrect and jump on to the pipe:
5. Fly up to the spot at the red arrow:
6. Have fun annoying the Alliance!
Have fun!
Edit: Widescreen is win :P