"I was recently asked why I constantly search for better RAM, when what's already installed in my PC is pretty darn fast. I explained that system memory is much like the tires of a highly tuned sports car. For everyday use we don't give it much notice, but when you need to do some fast racing, those memory modules can make a world of a difference. Just as the wrong type of tire can cripple a race bread Porsche, memory can sometimes severely limit the top speed of a highly tuned computer."
PCStats has a review of Crucial's Ballistix PC4000 DDR memory out, and they like it. It just so happens that this particular RAM is also included in my test system setup.