Its slightly old news now, but in case you missed it, you *REALLY SHOULD* go and check out the
Photoshop CS2 optimization guide over at
Extremetech. Many of their tips are pretty unique and not the pointless suggestions offered in other publications such as 'get a better PC/Mac, etc'. In addition to the obvious speed improvements, their advice also teaches you how to reduce the resource footprint of CS2, making it much easier to just leave Photoshop running in the background when not in use instead of having to shut it down and reload multiple times. Absolute gold-standard stuff!