If you use MySQL as a database server, you will definitely want to backup, so that it can be restored in case of any disaster. AutoMySQLBackuphas all the features I needed: it can backup a single database, multiple databases, or all the databases on the server; each database is saved in a separate file that can be compressed (with gzip or bzip2); it will rotate the backups and not keep them filling your hard drive (as normal in the daily backup you will have only the last 7 days of backups, the weekly if enabled will have one for each week, etc.).

More info: project homepage