What can energybending do? Aside from taking away someone's bending, as seen against Firelord Ozai, is there anything more to the energybending?

Do we know any details on the technique other than what was told in the series itself?
Not much is known about Energybending. Before the four elements and the avatar were created, Energybending was the only bending-art in the world. Out of this, the four bending-arts were created (Airbending, Waterbending, Earthbending and Firebending), so these are based on Energybending. Energybending is the base of all arts. While the for bending-arts are based on the Chi, Energybending works a little bit different: It bends the energy in general and not the Chi.

With that, Energybending can be used to take and restore bending-power and knowledge (nothing more is shown, but I guess that much more is possible):


Avatar Aang uses the ability to take bending-power from Ozai in the last episode of Avatar: The last Airbender. This is a dangerous technique, as the soul of the user must be completely clean; otherwise, it can happen that the victim takes over the user.
Both the lion turtle (in Avatar: The last Airbender) and Aangs Spirit (in The Legend of Korra) use Energybending to transfer knowledge to other people. I guess it's possible to take memories, too, but that's nowhere proven.
Korra uses the ability to restore bending-powers to help some victims of Amon. The spirit of Aang uses that ability to restore Korras powers.


Also, Energybending is the only bending-power that can be used by a spirit without a medium (as shown when Aangs spirit teaches Energybending to Korra).