In reply to Sorting data that don't fit in memory, tilly told me to try BerkeleyDB to fool around with large amounts of data. I have implemented stuff, and I'm not totally through now, but I already can say that Berkeley shows impressive performance. You can d'8 it at http://www.sleepycat.com. The distribution carries the perl interface. This DB is scalable and portable. Don't forget to specify a large cache.

Hope this helps,

Jeroen
"We are not alone"(FZ)