SSD drives are much faster...and much more expensive. I considered buying a small drive and new controller to handle the page file, prefetch and caching duties but the numbers just weren't there.  Not enough gain for the pain.

Depending on the age of you computer adding SSD drive to improve perfomance is akin to using a Ferrari for a taxicab, sure, you get there a bit quicker but the bottlenecks of parking, ofloading the passengers and traffic is still there. For the same cost of adding solid state drives ( and a drive controller to handle the capacity) you could buy a new box with coventional drives that would be significantly faster than your current machine. 

Solid state drives for consumers aren't quite there yet. Give it a couple of years for the prices to come down and the reliabilty to improve. Thas our plan at least.