I noticed that my last Linux sucks article wasn't clear about how I borked my Linux install, so I will explain what happened more clearly:
I installed CentOS 5.2. I like a distribution that works and will continue to work, complete with security bugs being patched, without having to reinstall the OS every 6 months. You know, like Windows. Also, I used RedHat from 1997 until 2004, and a combination of Fedora and CentOS from 2004 until mid-2007, so I'm more comfortable with an RPM-based distribution than a .deb-based one, since, among other reasons, Debian packagers are known to add security bugs to programs.
I then went to atrpms to get drivers for my wireless card. These RPMS are designed to work with CentOS/RHEL, and I only installed the drivers for my wireless card.
Anyway, the atrpms wasn't what borked my system.
What borked my system was going to mirrors.kernel.org, downloading the CentOS updates, and starting to install them by hand. You know, like how one updated RPM-based distributions for years.
It would have been fine if I had RTFM and did "rpm -e --allmatches --nodeps"; however I thought fixing this with rpm was impossible because "rpm -e -f" doesn't do the right thing ("-f" here really ought to be treated like "--allmatches --nodeps". Maybe one day I'll submit a patch).
Once I had the xulrunner rpm corrupting my database making "yum update" impossible, I did a Google search on various terms ("Same RPM installed twice", "Corrupt RPM database", etc) and the answers I saw told me to edit files in /var/lib/rpm by hand. So I did that, which completely broke things and forced a reinstall of CentOS.
And, oh, I do have some things in /usr/local/bin. Among other things, version 1 of the FVWM window manager and version 3.96 of the Lame mp3 encoder (which I feel sounds better than Lame 3.97). And, no, that isn't what caused the problem.