How do you do the offsite hard drive backups?
Depending on how much you need to back up I would recommend the following:
JungleDisk / Amazon S3 - Works VERY well.
RSYNC to a remote machine also works very well. CRON job every XX hours.
We back up almost a TB of data to Amazon's S3 cloud and have a "warm standby" at our colo backing up from the master several times a day (via rsync). The cost for transfer/storage on Amazon S3 is extremely cheap. (ie. cheaper than burning to a DVD but not cheaper than backing up to HDD. I know some folks who simply plug in a 1TB UDB "My Book" or something into the server and back it up weekly/monthly. Depending on your needs one or two of those might be the cheapest solution for you.
Now that's just talking about DATA backups. Several comments below talk about backing up the server itself...
Depending on your needs, Norton Ghost or even Acronis (http://www.acronis.com) might be of help to you. Things like Norton Ghost tend to rely on your ability to be able to actually turn OFF the computer to make the backup. Some of us don't have that luxury but if YOU do then Norton Ghost is a VERY good product.
Don't stop at just backing up the data--- we make regular Ghost images of our main servers, and keep those offsite as well.
Bit of a luxury I'll admit but we live-live our SANs and backup at each site with periodic tapes or disks going to an external company (such as IronMountain).