Geoffrey Grosenbach has recently posted an intro to memcache. memcached is a distributed memory caching system which can be used to speed up dynamic database driven websites by caching data and objects in memory (more on wikipedia).
Geoffrey even went so far as to write a shell script (use at your own risk) that will install memcached locally on your mac for development purposes.
Caching has really grabbed my interest of late and I’m sure I’ll be checking memcached out more in the future. For now, this nice intro will do.