Perhaps I'm the last kid on the block to come up with this, but I thought I'd share a neat little CSS trick I stumbled upon. In various parts of this site I use padding to make sure that, for example, text inside a box is separated by half an em from the border of the box. Putting a margin on the inside element doesn't work as well because you've got to anticipate every kind of element that might go in your container and give each one its own margin. The thing about padding, though, is that it doesn't collapse like margin does, nor do padding and margin collapse with each other.