Technorati's tag indexing has gotten me interested in having a full Atom feed for this site, including categories. So I downloaded the latest Atom module for Drupal 4.5 and then used Walkah's patch to modify the module to generate a full Atom feed. Then http://urlgreyhot.com/personal/atom/feed stopped working. Oddly enough, when I commented out the cache portion it worked again. So now I have an atom feed with categories here: http://urlgreyhot.com/personal/atom.xml

I recording the steps I took to do this because this module is not documented (as is sometimes the case with Drupal modules). Good luck:

1) Downloaded the atom module.

2) Downloaded atom.diff and saved to modules/atom/ directory.

3) Executed command in Unix terminal window: patch < atom.diff

4) Checked the module's output at http://urlgreyhot.com/personal/atom/feed

5) Created an alias via the menu "Administer > Url aliases" from atom/feed to atom.xml.

Thanks to Kika for providing the module and to Walkah for the patch. This is why I now send people who ask me if I freelance over to people like those Bryght guys.