I jumped ship from Windows to Mac, so I'm trying to keep track of the tips and tricks I learn as I go. I doubt there's anything groundbreaking here, but if you're a Mac newbie like I am, they might be of some use. I'm on 10.5 Leopard, so they might be different if you have an older version.
Finder Tips
Full Path View in Finder
Open Terminal, and type:
defaults write com.apple.finder _FXShowPosixPathInTitle -bool YESYou'll have to restart finder to get it to show:
killall Finder
Terminal Tips
Remove .svn dirs
find . -name .svn -print0 | xargs -0 rm -rf
Tell the Computer What to Say - Fun Factor of 10
say "my monkey's butt is covered in crisco!"
My kids think this is hilarious, and I insult them via the Terminal almost daily
Keyboard Tips
Command + Tab: cycle through apps you have open
Command + ` (tilde key): cycle through windows in the same app
Command + Shift + g: go to a certain folder. Handy for Finder or other programs where you don't want to navigate through a bunch of folders to get where you wanna go.
Command + Shift + h: go to the Home folder in Finder or the file browsing window.
Command + Space: Open Spotlight, for quick searching and app launching.
Speakable Items
I'm not quite sure if I had to do something special to get this turned on, but if you select a chunk of text and hit Command + F1 the computer will read that text to you. I often crank the volume up and have the computer read a web page to me while I fiddle around the house.