MACSPECTRUM,
Having researched CopyAgent, I'd say your current alternatives would be Dantz Retrospect (which has limited functionality in OS 10.3.x) or Apple's Backup 2. The other alternative would be to use a second HD, reformat/re-install and set up a RAID 1 (mirrored) array with the 2 drives.
The software alternatives might be intrusive because of interruptions when launching and running, but the mirrored array would be a "behind-the-scenes" method of performing such frequent back ups, as the system is continuously writing all data to both drives. The downside to the latter method is, should you have a catastrophic hardware failure (which carries very slim odds), you might lose data on both drives. The only solution is daily back ups of the mirrored array to another device, preferably archival.
I'll reiterate my set up because it doesn't get much safer; main system RAID 0 (striped for speed) is backed up daily via Backup 2 to external Firewire RAID 1 (mirrored for redundancy), which in turn is backed up to CD as needed (weekly). A second internal RAID 0 on the secondary system bus is a clone of the OS X volume via Carbon Copy Cloner, in the event I'm forced to perform a re-install of the entire system. Perhaps my methods are a little aggresive, but the peace of mind I receive is well worth it.
Now I'll simply get nosy.

Why the hourly back ups?