Oh, and one more thing about SSD's - the speeds of SSD's vary widely, from the very-slow to the very-fast, and is largely dependent on the disk controller that is on the SSD. You want to look for Intel's 2nd generation drive (Intel X-25M's), or drives based off of Indilinx controllers (e.g. the OCZ Vertex and Agility drives). There are even preliminary tests off of a new controller from a company called SandForce that is supposed to knock the socks off of everything else, once the SandForce-based products actually hit the market in the next few months.

If you buy an SSD based off of any other controller besides Intel, Indilinx, or SandForce, there is a good chance you will get a $hit drive with performance lower than a single 7200rpm mechanical drive. If performance is king, then avoid drives based off of JMicron or Samsung controllers.