I recently purchased a 2TB WD MyBook external hard-drive with the intention of installing Ubuntu on it in a way that will allow me to simply plug it in to any computer and boot MY Ubuntu from virtually anywhere. I now realize I should probably have consulted folk here before buying the HDD, but it's too late for that now.
I installed Ubuntu as I usually do, but it didn't work. After some investigation and much tweaking I managed to boot it -- once -- on my brother's laptop. Now I can't do that, and I still can't boot it from any other computer.
I'm perfectly willing to format it and start again. What is the best way to do this, preferably without using a LiveCD (as my own laptop doesn't have a CDROM)?