I currently have 2x 60gb Agility SSDrives in my desktop, and I must say it really is all the hype you hear.
Installation is simple, most higher end cases have a slot for SSDrives, or they sell mounting racks as well.
One thing to remember with some SSDrives is that you need to put it in the very first SATA port, or some will have issues recognizing it if you plan to use it for a boot drive (which you should).
I originally had a 10k RPM SATA drive before I switched to SSDrive for boot, and I must say you can instantly notice a difference, especially if you have a high end system. I can boot up windows 7 from bios to desktop including login in about 4 seconds on average.
For my setup I use one SSD for boot drive, and nothing else. The other SSD I use for installing heavier applications that have any noticeable speed delays, eg: photoshop, games with loading screens etc. I then have seperate SATA drives that I use for installing everything else, file storage, etc.
Specs for reference are: 8gb RAM, win7 pro x64, intel i7 extreme, n480.