Pim Backup 2.5 is free.
Many people use it, and I have cooked into every ROM I've made.
Works like a charm. I have it scheduled to backup all my PIM data every morning at 6am and save it to the storage card. I set it to keep the last 3 backups incase something gets screwy.
http://www.freewareppc.com/database/pimbackup.shtml