Following are various tidbits I have collected/created about databases.

• "Free Database" Comparison - Oracle, IBM, Microsoft
• Neo4J - a graph database

XE is a useful database, and is great for small applications. Once I needed to move an entire software project to another machine in a 3-hour window. Here is the 2-part strategy I developed.

• How To Backup an Oracle XE Database
• How To Restore an Oracle XE Database