My favorite CSS trick, or rather, the mechanism that underlies a whole bunch of tricks.
Contextual selectors let you specify rules for a class, then override them when the occur in a given context. Using this, you could re-define hover styles for links in tables, links in ordered lists, links in h1's, etc.
This meshes with good programming practices when you have code generating HTML. You can have low level code assigning simple classes to the elements it generates, and have control over the look of those elements without having to pass context parameters.
context selectors
Dated: 08/19/2003