1. Mount X-53 (Chopper works also but not as good)
2. Get your friend in the backseat, prefer resto druid with nature´s ward talent.
3. Toggle walk mode.
4. Backpedal toward the monster slowly so your passenger will get the agro. Relese the button when passenger is near melee range. If you were close enuf your friend now has the agro, if not then hit backpedal to move inch at once untill hes agroed.. DO NOT JUST DRIVER OVER THE MOB
5. Gather more mobs!
You can toggle run mode on for a sec or two to make it faster. For some reason the agro wont reset if they hits your friend while hes passenger and driver is in walk mode.
Not that super "exploit" but maybe someone wants to gather tons of low lvl mobs with aoe and gets lowbies killed or something.
Another mount trick
Put follow on your passenger (if using mammoth the passenger gotta be on right side seat) and you will start to spin like mad automatically (trying to follow own tail).
DOES NOT WORK WITH EVERY RACE.
Works as orc atleast.
Stare the screen and get dizzy... or DC.