A quick update - the Info-Mac archive site at <sumex-aim.stanford.edu> is back up and running, although you should still try to use mirror sites whenever possible.
Thoughtful, detailed coverage of the Mac, iPhone, and iPad, plus the best-selling Take Control ebooks.
Constant Dictionary Definitions
If you hold down Command-Control-D in a Cocoa-based application that supports AppleSpell, you'll see little dictionary pop-ups for each word that you mouse over. Neat, eh?