From TidBits: Our Favorite Hidden Features in Mac OS X Lion
“A major operating system update is a large, complex beast (and in this case, one that roars and eats gazelles for lunch). Apple touts top-tier Lion features like Launchpad, Mission Control, and extensive gesture support, but hundreds of improvements and changes abound. We’ve collected an assortment of fun and useful tips that you’ll want to try during your first few hours with Mac OS X 10.7 Lion.”
They can all be found here.