I add items to this list when I discover configuration tips for the Apple OS X operating system that I personally find useful. It is not meant to be a comprehensive list of everything you can do to customize OS X. It is mainly a record so I remember what customizations I've performed, so I can potentially undo them later and/or repeat them on new computers or after major OS upgrades.
Good resources for more Mac OS X configuration tips are macosxhints, OSXDaily, lifehacker, and the official Apple Support site – some of the tips I've listed here were either initially researched at one of those sites or ended up archived there later. Some of my tips were emailed to me by helpful readers (thanks!), and others I have worked out (sometimes painfully!) myself. No matter the source, I have personally tried, tested, and used all of the tips described here.
Additional useful OS X sites and tips from around the web: