EDIT: Now has a SpaceDock page: http://spacedock.info/mod/288/BackgroundProcessing. The SpaceDock page is the best source of information on what the mod currently does and how to use it. I'm working on a little mod/library to make it easier to write PartModules that do something when a vessel is not being actively controlled by the player - say, because they've left it landed or orbiting and gone back to the space center, or undocked it, whatever. For an example of mods that currently do so