My wife is of the opinion that if my Mac mini is slow, it probably has to do with what all I have loaded on it. Fair enough, as I am using a (mostly) unmodified version of the default personal Web server for testing purposes. I have resisted installing MAMP because there is a perfectly suitable Apache+PHP server built-in, and MySQL runs as a service in the background.
I finally succumbed today when I attempted to install Magento for testing and the GD and mcrypt libraries were missing. As I do not feel up to learning the ins and outs of compiling PHP, I went ahead and started MAMP. Maybe the next version of Leopard (due out in 2009) will have more of these features enabled by default.