Gas Powered games is currently looking at open sourcing the siege engine which is used for games such as Dungeon Siege, Demigod and more recently WildMan. In short this would allow us to make Action RPGs allot faster and better than before!
If you want to learn more about the capabilities of the siege engine look here.
The rendering part of the engine is currently being updated for more modern effects.
If this interests you Consider pledging towards wild man which will utilize the updated siege engine.
This information was obtained through a Q&A with some developers at Gas Powered Games.
If you have questions about the Siege engine or WildMan visit - Gas Powered Games
Also the Gas Powered games Developers are having a Live stream on the 4th of February @ 1PM PST (Pacific Time) Link