Hard Drive Backup via Amazon S3
Amazon has this nice service aptly named Simple Storage Service (abbreviated S3), where they aim to provide simple storage of data of arbitrary size, with high availability at consumer-level cost. It really is a nice design. And there's a REST interface setup for me to store my data!
And Jeremy Zawodny points out how using this service actually ends up to be cheaper (and more reliable) than having a home media server!
That puts the total cost for 5 years worth of backups [on a home backup server] around $2,275 assuming that no hardware breaks.
Switching to S3 could save me $587 over five years!