Mainstream SSD's have been around for a year or so now, but Intel has recently come out with their X25-M SSD which can outperform conventional hard drives by up to 175 times! The bigest bottleneck in the computer today is the hard drive, all of the moving parts take time to work. When you hear your computer clicking and chugging along, it is reading and writing information on the hard drive. These new SSD's have near instant read and write speeds, so now when you open up microsoft outlook, it just instantly appears, or if you open a new browser window, it's there in a split second. This is going to change the computer as we know it. Prices on the X25-M are a little high for the amount of space you get, if I were to build a pc with one, i'd use it for the OS hard drive, then add a conventional drive for file storage.
Here's a benchmark example of the X25-M:
Notice how the X25-M overall hard disk score is almost 10 times as fast as a normal hard drive. More importantly, look how the overall performance of the already pretty quick T9600 cpu computer Doubled just by swapping the hard drive with the X25-M.
Intel has done a great job with this product, i can't wait to build a few machines with these drives.