My main PC is regularly backed up to tape. That backup includes all the programs and files that are necessary to reconstruct the remote control and the server PC, with the exception of the music files. The music files are much too large to fit on normal backup tapes, and the cost of the professional tape drives that store hundreds of gigabytes would be prohibitive. It isn't strictly necessary to back up the music files, because they can always be re-created from the original CDs, and the tags re-inserted from the Media Center database. But that would be such a long and tiresome job that for me it's worth investing in an extra disk drive to back the music files up.

For backing up the music files I have a Western Digital NetCenter disk drive, 500 Gb, the same capacity as the large hard disk in the server PC. I use the Directory Synchroniser to compare the contents of the drives and copy any new or changed files to the backup drive. The synchronisation process runs automatically every night, under the Windows task scheduler.

The backup disk drive is stored in an outbuilding, so that fire or theft wouldn't affect both copies of the music. It's connected to the network by the domestic mains wiring, using a pair of Netgear HDX101 powerline adapters.