There is an abundance of mobs in the Tol Barad cell blocks with quick respawn times and valuable drops (cloth, greens, silver). However, as the available block is usually farmed for quest objectives, there is no way to grind the mobs.
What is not so obvious is that the creatures in the other blocks still spawn. All you have to do is get through the gate, which can be done very easily using ZatXYZ (courtesy of maclone).
Having an entire block to yourself, with plentiful mobs and fast respawns, can generate a pretty profit from all the gold, cloth and boe drops. Potion of Treasure Finding - Item - World of Warcraft does work and should be used.
Obviously there is a risk involved, as you will have to break the ToU to get there. But it is not likely you will be noticed.
Happy farming guys.