looking for inexpensive solution for backing up files on hosted server

There are so many free and low-cost options to backup desktop files on the cloud (Moxy, CrashPlan, SpiderOak, etc.). Doesn't seem like any of these support servers (e.g. remote monitors). Anyone know of an inexpensive solution to provide online storage (for backup purposes) for Linux (specifically CentOS) based files/directories? I see companies like

http://www.serversurgeon.com/managed-backups.html charging $30/month for 30GB for managed backup. Anything out there where I can self-manage or have the software auto-manage and save some money (e.g. like CrashPlan, Moxy, etc. but made for servers-hosting market) using CentOS server?

Thanks in advance.

We host a bunch of servers for ASP customers. Been thru the wash/rinse/spin cycle with various online providers like idrive, mozy etc. We've settled on jungle disk (IIRC they have a linux client). Price was not a consideration (never trust your backups to the cheapest vendor) but they were more reasonable than most, and with the de-duping of files and compression we use very little actual storage. Most of the vendors we found were focused on home users or small businesses and had very poor client software to support server systems