Best Online Remote Backup Service w/Linux Client?

technocraft asks: "I've been searching for an online service to backup data from my Linux file server and have come up with nothing. For many users, Carbonite looks to be a great solution: Affordable, with 'unlimited' capacity. Unfortunately for me, you can only backup from Windows XP and explicitly NOT from external drives or network mapped drives (like my file server)." Is anyone aware of an online backup services without these restrictions?