I found something like 5-6 legendaries last night, including some dex ice climbers. Some guys I occasionally run with figured this out:
Start in act I, at the festering woods episode where you have to get the two orbs. Run to the crypt of the ancients, clear it, kill the elite, then tp back to town to create the waypoint / portal. Exit the game, re-start, and you'll have a TP point to the crypt of the ancients. Clear, repeat.
We did it on MP10 about 10-12 times. He was a 400k dps DH using grenades for area damage, I have a 210k dps DH using bola, spike traps, and marked for death with grim reaper for area damage, and we had a monk at 170k dps who used the vortex skill (whatever it is called).
We'd run in, find the elite, I'd cast marked for death on him, we'd surround him, drop some protection turrets and go to town. The guys who spawn all those skeletons were nice for huge amounts of kills too. Got tons of xp and oh so many legendaries.