My buddy Keith has way too much time on his hands and not too mention way to much memory for his laptop.  Keith recently got 8gb for his t61p and he got bored.  Take a look at what he did to that poor little laptop, when he loaded Server 2k8 and Hyper V on it:

Running A Bunch Of Vista SP1 VMs on Hyper-V With A Single Laptop  

Pretty awesome stuff even though he is not sharing his 8gb of memory with me. :-)