Installation with Software Raid

[Jonathan Hudson]

I've been presented with a new machine with 2 120GB SATA drives. I think 
  I'll like to RAID1 these, but I unsure of the best way to do this.

One big / doesn't work; Ubuntu says it can't boot with / or /boot on 
raid. The often referenced Gentoo HOWTO describes a scenario with / and 
/boot RAIDed.

It seems that I must therefore create separate /usr /home /var /opt etc 
partitions and separately map these onto md devices ?

Comments, advice, pointers to HOWTOs etc gratefully appreciated.

-jonathan