Ten CSS tricks you may not know (plus critique)

This article is from CodeProject again. It's a superb article about some interesting stylesheeting tricks. The ten CSS tricks are:

1. CSS font shorthand rule
2. Using two classes together
3. Css border default value
4. !Important ignored by IE
5. Image replacement technique
6. CSS box model hack alternative
7. Center aligning a block element
8. Vertical aligning with CSS
9. CSS positioning within a container
10. Background color running to the screen bottom

Here's the article: Ten CSS Tricks You May Not Know by Trenton Moss ... and here's a critique and improvement of the article by Tantek Çelik. If you're going to be seriously using these tricks on a regular basis I highly recommend reading the Tantek improved version also (even though I think it's a little harsh on Trenton Moss).