I’ve enjoyed Chris Breen’s appearances on TechTV, which led me to his Mac 911 Weblog. Recently he pointed out that we can run routine maintenance from the terminal with: sudo periodic daily (or weekly or monthly). Works a treat!
Update October 2008: the link at http://www.macworld.com/weblogs/mac911/archives/2004/04/000139.php?lsrc=mac911blog no longer works. Thanks to Tim for pointing this out.