This is technically an exploit, I am not sure if it is a bannable offense, but it has been done on my realm and none of those players have been banned.
In short: this is a way to gank and kill your own faction, and make them ressurect at a spirit healer.
Step by step guide:
1. Be in decent pvp gear so you wont be one shotted by any joe
2. Group up with a few other people, and at least one warlock.
3. Find someone you Hate. That's right, has to be a capital H.
4. Have the warlock message them, and offer them some outlandish amount of gold or a large incentive to help you with a quest in either Blade's Edge Mountains or Nagrand.
5. Depending on where you chose, be on the roof of those zone's respective arenas.
6. Have the warlock summon them to the roof.
7. Remove them from the group
8. Kill them
9. They have to rez at a spirit healer. They could call in a healer, but he won't last long
10. When their guild or the cavalry comes, fly off with flying mount.
If anyone does this to you, just have a guildie queue you up for a battleground, and it will rez you without the repair bill.