LIT books can be de-drmd (and converted to HTML) with Convertlit; lit's DRM was possible the first commercial DRM to be cracked. Convertlit will run portably and is amazingly simple to use; no actual script skills required.

iBooks are still uncrackable; I tend to think this is because you can only read them on iThings, and you can't run scripts of your choice on those. They'll eventually be available on PCs because Apple will need that market share as soon as competitive tablets show up, just like Kindle gave out Kindle-for-PC as soon as the Nook hit the marketplace. After that, with books & key on a computer that allows real programming, someone will figure out where in the digital file the key is buried, and how to unlock the book.