Friend and I used to kill melee on Great Lakes for money. As far as I can remember:

Liches: 80k/hour good weapons
Lich Lords: 100k/hour good weapons and regs
Air Elementals: 50k/hour (This could be done while sleeping nearly)

I remember doing Teraths, Dragons, and Balrons with magery, but I don't recall the cash.

The best money ever, however, was stealing silver vanqs in the lich lord room. We'd score a SV per hour along with several others consisting of either Silver Power or Vanq. I guess this just doesn't apply to player run shards though...

What is it they say about silence being golden?