Ward and Bjorn have put out an interesting plugin for Eclipse called Eclipse Monkey. I bugged Ward after he joined Eclipse to please do something about the dearth of scriptability in Eclipse. This seems like the start of something interesting, but at the moment feels a bit too much like a toy.
It doesn't help that I have almost no experience in writing Eclipse UI plugins. Even the stuff the Find_System_Prints.em is doing is a bit over my head; in terms of what the 'doms' are doing, anyway.