In a nutshell, swap is hard disk space used to hold data when there is not enough physical memory to accomodate all the processes running on the server. Swap isn't necessarily a bad thing, though it's slower obviously due to the physical read/write process to the drive.
Cobalt-Serve, add more memory. You've got 192MB, must be a 128MB + 64MB configuration. At a minimum, replace the 64MB SIMM with a stick of 256MB server grade RAM for $40. That's the obvious solution for you.
Waverz, what are you using your box for? What model is it, 3 or 4? I'd bet you've got an overloaded box, or a poorly coded application, or a (mis)configuration issue that's causing your problem. You'll need to fix what you've got, or if that's not the problem, upgrade to a new platform with more capacity.
If you need swap space on a Raq and have 512 mbs of ram, id recommend moving some sites off instead increasing the swap.
Or check what drives the memory crazy.
On raqs its usually the analog logrotate and parsereport.pl that runs everyday causing the server to scream high on ram when there are lots of websites. Ortherwise, the logrotate is not working properly.
Ive also realized running the scheduled default raq backup utility everyday is not a good idea if you have lots of sites.