I've added category feeds in addition to my main blog RSS feed.
If you're interested in doing the same, here's the code I used in my Sidebar template:
<?php wp_list_cats('sort_column=name&optioncount=1&feed=RSS&feed_image=icon_url'); ?>
The command shows the Category list alphabetically, along with the archive count, and an image link to the RSS feed. To do the same on your WordPress blog, replace the icon_url with the your own image URL (ex: http://www.this.com/that.gif). There's more template tags available in the WordPress Codex, so go nuts.
The resulting list looks like this:
So, if you like it when I'm geeky but could do without the football talk, there's probably a category feed or two of interest to you.