I love keyboard shortcuts and accelerators. Usually I track them down on my own, once I've started using a feature often enough in an application to warrant it. But, every so often I'll accidentally hit just the right combination of keys in an application to launch a shortcut I wasn't aware of. Usually, it's something I don't really want (I often curse ctrl+d in word 2007, when I really meant to hit ctrl+s). Very rarely, however, it's for something I actually find useful. Today that turned out to be alt+click on a document in Word 2007. If you alt+click on a word, it will launch the references panel, providing instant access to a dictionary and thesaurus (and a host of other potentially useful reference tools).
One word of warning- I'd suggest against using this shortcut if you are working on a Word 2007 Blog Post. I just tried it to double-check something, and it seems to crash Word 2007 about half the time on blog documents. It seems perfectly stable in normal word documents.
(By the way, I still haven't found a reasonable way to use images with Word 2007 + Blogger. I'm still manually coming in later and uplaoding images through the blogger interface. Has anyone figured this out yet?)