RAID is nice, but apparently it's tricky to set up. You have to press F6 when prompted during Windows Setup, and do a bunch more stuff. I'll do it at some point, but haven't yet.
What I'm going to do is just get one Raptor for my OS and programs. I have a 300GB 7200RPM 16MB cached Maxtor external hard drive. If the 16MB Maxtor drives are comparable to the Raptor, I am disappointed, because the Maxtor isn't all that fast, but I didn't buy it for speed, I bought it for capacity. Since I have a laptop and will soon be building a desktop PC, an external is ideal as it can be swapped between the two, or put in the bag with the laptop and taken across the country.
If you got 2 Raptors and didn't RAID them, you could have your OS and programs on one and your pagefile on the other. That would work pretty good.
A note about installing programs and games on a second hard drive (not the system dir) that's all well and good, but if anything happens to the system drive, the game might become unusable! It depends on how much the game or program depends on the Windows Registry. For example, long story but I have the game Deus Ex in a ZIP file. I don't install it, I merely unpack it. Nothing for the registry. This is totally safe to have on another hard drive. I could run it off my external if I wanted. Now let's say a program relies heavily on the Registry. You have a problem with Windows, you reinstall it (and thus rewrite the registry), and now your program starts acting up. Some programs work off INI (configuration script) files; these are better suited to work off a second hard drive, but if you reinstall Windows, you'll just have to re-create the file extensions that program may have had.
(I know, Reformatting and Reinstalling Windows is a hobby of mine...)
AMD Athlon64 3200+ S939
1024MB Dual Channel DDR400 Corsair XMS with LED activity indicators
256MB GeForce 6600 PCI-E by Chaintech
Aspire X-Navigator case with 500W PSU, 6x80mm fans, 1x120mm fan
Gigabyte nForce4/PCI-E S939 mobo
80GB 7200MB 8MB WD IDE HDD
16X DVD±R Dual Layer burner
Memory card read/writer
...and a Led Zeppelin sticker!