Because I can't find a good PHP editor for OSX, I develop in Windows with PhpEd. At the moment, my development time is split between a desktop and a laptop. To partially solve the problem of having 2 different environments, I have installed a virtual machine (through Virtual Box) and put the hard drive file on an external hard drive. At the moment, I've been connecting it through Firewire 800.

I have 2 problems with this setup: (1) The hard drive is fairly large so to carry the laptop and hard drive I pretty much require a backpack. (2) The hard drive requires quite a bit of power and therefore reduces the battery life (by about 40%).

My thought is to move the VM hard drive onto a USB key. I realize it will be slower, but as I'm just using it for PHP development, there isn't a lot of disk activity in the VM. The only really intense time is boot up, otherwise, it just about sits idle.

Do anyone have any suggestions on a USB key to use for the VM? It would need to a minimum of 32GB.