IBM has announced a new technology capacious of double RAM through a new compression system. ServerWorks (a linked society of Broadcom) has saled frists server's chipset whit Memory Expansion Technology (MTX). It Isn't a new idea, beacuse already exists similar technology, but IMB has announced of a ratio between 2:1 and 6:1.
Memory eXpansion of IBM is a chip between CPU and RAM capacious of compress datas in a little span. Big Blue has also insert a special cache of 32Mb for contains frequently datas.
Chipset of ServerWorks are used also by (whit Intel architecture): Dell, Compaq and HP.

related links:
www.serverworks.com
http://www.research.ibm.com/journal/.../tremaine.html