I am quite disappointed when Tom's hardware says the DDR RAM would have cost almost double the price of conventional SDRAM. To me it is not. Alright, I admit I can't find PC2100, but have a look at the following price which I have compared.
256MB SDRAM, PC133 CL=3 $89.99
256MB SDRAM, PC133 CL=2 $94.49
256MB DDR PC1600 $94.49
256MB DDR PC2100 "Will soon be available"
Is DDR-RAM double the price of conventional SDRAM? Not at all, I should say.