I want to have a USB that boots Ubuntu as you may have gathered from the title. But, the only USB that I have available is 4GB. What I want to know is. If I install Ubunto onto the USB will I be able to use the remainder of the space as storage?
Haven't testet it, but that should work. I'm pretty sure a friend installed it on a 4gb stick too. But remember: Whatever you are writing to that disk (packages etc), writing on that usb stick will be quite slow
Although, I must ask: why do you only want it on your USB? If you want to play with Ubuntu on your computer, why not just install VMWare Player? It's free if you register. Or, you could even use VirtualBox.