Hopefully the CalXeda ARM-architecture processors will soon dominate in Datacenters for web applications so power efficiency in ARM-processor server architecture will outcompete the x86 server architecture.

And just think how small web servers will be when CalXeda ARM-architecture will be mixed with IBM 3M 3D tech solution for stacking processors together with solid memories like the Memristor or other types of RRAM memories forthcoming years!
But PCM,MRAM,FeRAM and Nand Flash solid memories will develops more to.

IBM 3M 3D were announced in September, this animation is 0:38min. short.
http://www.youtube.com/watch?v=GjvIdQGfO_0 

HP Labs have developed the Memristor but they are not the only developers of memristors
for instance the Memristorproject.
http://www.memristorproject.com/ 

HP Labs manager Stan Williams is good to explain how the memristor works.
This video is 6:02min. short.
http://www.youtube.com/watch?v=rvA5r4LtVnc&feature=fvwrel