With the new version of OS X (Leopard) Apple has included some great functionality in Time Machine. Your Mac will automatically backup to an external drive every hour. It includes the ability to recover deleted files in a timeline.
Zotero [zoh-TAIR-oh] is a free, easy-to-use Firefox extension to help you collect, manage, and cite your research sources. It lives right where you do your work — in the web browser itself. Features Automatic capture of citation information from