Simple one that we've been using since the game launched.
- Get Hatred's Chosen (this is achieved by killing 10 players or otherwise getting 100/100 while bloodmarked).
- Have friend join your party and run to you in the zone.
- Unparty and hit your friend as fast as possible--best classes for this are barbarians, crone claw druids and rogues with flurry.
- Don't kill your friend but just keep hitting him. Every hit will give additional seeds of hatred.
- Continue for 5 minutes. Our record is 1.1million seeds which actually required me to go to town, gamble and return back to do another turn-in to get the additional remainder as the Red Dust cap you can hold is 750,000
You can gamble all 5 primary armor pieces for 3,000 dust each. This makes this exploit by far the easiest way to farm high-end gear in D4 quickly---provided you can maintain a killstreak in PVP (or win trade it).