This is really minor, but I thought fun. I needed to check something on the .mac web site, and without even thinking about it, in the IE address bar, I just typed .mac and it worked.
I am used to (with .com addresses) skipping the http://www and the .com, so for Yahoo I would just type Yahoo, but I never thought it would work with .mac. Cute.
[Editor's note: Oddly enough, this doesn't work if you try ".cnn" or ".yahoo" or ".anything_else." Just .mac ... anyone know why?]
Mac OS X Hints
http://hints.macworld.com/article.php?story=20021007053832435