Autoloot was introduced in Patch 0.10. If you <Shift>+click on a mob, chest, or other container that has items, you will automatically loot all non-bind-on-acquire items. You can also use the same method to automatically mine a vein, harvest herbs and since Patch 1.2 to skin an animal. This is now settable as an interface option as of Patch 2.0.1, so that you might default to autoloot on a right click, without having to shift-right click to loot manually.
AutoLoot used to be an addon for Cosmos, later removed.
|Autoloot How to! TGN.TV on YouTube|