Top Cat allows you to specify a main category for your posts. Even though WordPress posts can have more than one category, you may want to specify whi
Suppose you have a post about the Cannes Film Festival, and another about a French film. Both might be in the "France" and "Films" categories, but perhaps you'd want to put the film post mainly in the "Films" category and the Cannes post in the "France" category.
Using Top Cat's template tags, you can then style the posts differently based on their main categories. For example, see my home page at http://www.thunderguy.com/bennett/
The administration functions of Top Cat currently don't work on all browsers, especially older ones. I plan add universal support in the near future.
Have a look at the code... It's slightly tricky because Windows Internet Explorer works differently to the way you might expect.