Alright. This is my first original post in about 4 years so bear with me.
My brother and I are RAFing and we got Gnomeregan as our random. In Gnomeregan the item Grime-Encrusted Object drops from nearly every trash mob in the dungeon. Go there as a low level, around 30. Once you and your party or friend have cleared the trash mobs or the whole dungeon and have racked up on Grime-Encrusted Objects go to the The Clean Zone where you will find The Sparklematic 5200. The Sparklematic 5200 gives the quest The Sparklematic 5200! It requires 1 Grime Encrusted Object and 3 silver. The quest is repeatable so you can farm Gnomeregan up to 5 times and hour with the reset and turn them in constantly and hit exalted in a very short time as a low level character.
Summarized:
1) Take a friend or party to Gnomeregan.
2) Farm trash mobs and loot Grime-Encrusted Object
3) Go to The Clean Zone
3) Accept quest from The Sparklematic 5200!
4) Turn in with 1 Grime-Encrusted Object and 3 silver each time
5) Farm until you hit exalted
Edit: This only works if the quest is in your level range a.k.a Gnomeregan queueing range. The quest does not give rep at level 85. The best method is to get to Gnomeregan on a level 85 (difficult for Horde) and farm the hell out of Grime-Encrusted Objects. Then mail to your low level alt and turn them all in.