Ya, the Shear tool is very useful, although I rarely use it, since I do basically all of my editing in Photoshop. I really only use Illustrator for text and vector based graphics, like monograms.
Have you tried the Displace tool yet? It’s really cool once you get the hang of it. It’s probably the most complicated tool to use because you have to first do all these adjustments and save your file separately before you even begin the displacement process.
How’s Painter? I’ve noticed that some people love it and some people just don’t really have a use for it.
Also, in case you haven’t seen it yet, check out this guy “Hamsterfly” on DeviantArt. Amazing work.