I like Quake 3. It’s still one of my fav FPS games. I have the Linux, Mac and Windows binaries installed in my licenced (yes I bought the game) install directory of the game. However, it is getting a bit dated, and computers have come far enough where you want to make sure you have every possible settings in Q3 turned up to the highest.
Most of the documentation on the web points to adding the q3config.cfg or autoexec.cfg files to the baseq3 directory in your installation directory. This isn’t quite right in MacOSX. Mac OS X stores the config files for Q3 in the ~/Library/Application Support/Quake III/ directory. You’ll find your q3config.cfg file there.
Also, if your graphics card isn’t properly supported (the 8600GT on my Macbook pro is not) then Q3 will attempt to use the default driver. The default driver is actually software rendering. It will make your CPU hot. And it will look like Duke Nukem. No pretty textures, no detail. If that happens, Macs seem to have the Mesa OpenGL library installed, which identifies in Q3 as the Voodoo driver. Just change the driver in the settings to use that, and you’ll be good to go! Unfortunately that restricts me to 1024×768 on a monitor that normally does 1440×900, but it still looks way better!