http://www.newegg.com/Product/Product.aspx?Item=N82E16820231098 DDR2 prices are insanely low these days. Having anything under 2GB is now officially unforgivable.
http://www.newegg.com/Product/Product.aspx?Item=N82E16820146565 Better ($28.99), if you don't mind playing the rebate game.
Another great buy: http://www.newegg.com/Product/Product.aspx?Item=N82E16820609026 $39/29AR for really low latency RAM: timings are 4-4-3-8 Think I'll be getting this for the one I'm building.
DDR3 supposedly has real world, noticable benefits already (unlike early DDR2 due to much higher latency than DDR). However.. once you see the price gap, and the limited mobo support, it's a bit absurd to go with DDR3. Of course, the downside is that our nearly-free DDR2 is on the way out
Noticible benefits only if you're willing to pay for at 3+ grades of speed higher than the DDR2 it replaces. So you need DDR3-1333 to get better than DDR2-800. Not worth it, IMHO.
