There is a cool trick to own a person on your faction if you are a rogue or druid. (Better is Rogue if you don't wanna die too.)
1.) Say your friend you wanna test arena with him with a non-rating game.
2.) Invite him in your Group.
3.) Go stealth in a city of enemy faction to the "PvP-Area".
4.) You will see the Goblin for the Arena is friendly, invite your group to the waiting-line for non-rated arena fast before the other NPCs killing you.
5a.) If you are a rogue:
Do valnish and hope it is not bugged and go outside of the "enemy" city.
5b.) If you are a druid:
You got a problem because you will die. (So its only usefull if you are really a rogue)
6.)
When Arena Pops-Up do not join the arena. Only let the other person join.
7.)
Volla. The person you want to own got owned! First he lost in Arena because he is alone, and when he leave arena he will spawn in the PvP-Room in the enemy faction and he is dead in few seconds^^.
Note:
This is really just usefull if you are a rogue because you can valnish. But its able with druid too.