I was reading an article in Electron Design (04/14/05, pg 46) about DRAM speeds ("DRAM Advances Splinter to meet many system needs"). I was amazed at the new speeds for DRAM. I thought things stopped at about 166Mhz. Apparently not so. There is now DDR, DDR-2 and soon to be DDR-3. The seeds go from a pedestrian 100Mhz up through 1.6GHz. Last time I checked 1.6GHz was RF territory. I guess you need to be an antenna person to design SDRAM layouts.
I was confused, so I made a little table. It scared me.