In wrath the Death knight begins at level 55 and through the starter quests easily reach lvl 58 solo, probably 59+ with RAF triple XP. The DK also gains an average of 40G from these quests in addition to drops.*
If you have a RAF account with at least one 55th level character (and TBC/Wrath installed) your DK will be able to bestow one level upon reaching 57 and another at 59.
This means that you can grant two levels to any toon lvl 59 after just 2 hours work, at most.
After granting those levels you can vendor all your gear, send that cash home to your main, and delete the RAF DKs. Rinse and repeat ad nauseum.
I think the profit of 80G (40G per toon) and 2 levels to another toon are well worth 2 hours time.
Short version: Regular and RAF accounts make Death knights together, Level to 59 through starter quests, grant 2 levels to any toon 59 or lower, then send gold home before deletion and being remade.
*I began a DK in beta tonight and on my 3rd kill Hurricane dropped, 10 minutes later Golemshard leggings dropped as well. This indicates that, as of now, the loot tables for the DK zone are at least as good as normal areas of lvl 55+