Cache in meinds? See discussion and links:
http://www.geocrawler.com/archives/3/14838/2001/8/0/6497634/
http://www.geocrawler.com/archives/3/14838/2001/8/0/6497652/
http://www.geocrawler.com/archives/3/14838/2001/8/0/6502830/
http://www.opensymphony.com/oscache/