In cataclysm areas, Mount Hyjal, Uldum, Twilight Highlands, Deepholme, or Vashir, Can you get epic items for lvl 85s on mobs? Just random guys? Not the ones in the raids but just normal guys that have little health.

ya you can there called world drops they can drop off any creatur in the game as long its in a level range like all lvl 85 mobs might drop an item that is worth 50g!!!! and i have also noticed that since cata world drops drop more so u get more money too if u dont want them!!!

Yup yup. The Pant Thief guy in Twilight Highlands dropped Gilnean Ring of Ruination for me.

Dunno about the new areas, but before cata there used to be a fair number of epic 'World Drops', that one could get off any monster of the items level.

There also used to be dragons that would show in in certian zones from time to time, and most took a group or raid to defeat, they dropped powerful epic stuff.

you might be able to get stuff off a rare, if you run into one.