I was able to make a live USB stick of Ubuntu 10.04 using Ubuntu's built-in tool. But I learned the hard way that updating Ubuntu then results in an unbootable stick. I've read in these forums about users who have performed full installs on USB sticks, but when I run the installer from the Live CD, I don't see the option to install on a USB stick. Yes, I had the 8GB stick plugged in while running the installer from a CD, but all I saw as install locations were the /dev/sd<n> (hard drive) partitions.
Setting aside the debate on how soon the flash memory will wear off, here's what I'm wondering - assuming I can find out how to do a full install onto the USB stick.
Does a full install makes your USB stick un-portable? Can you still plug the same stick on your desktop and laptop PC's and run Ubuntu on either, or is the installation tied to the hardware where you first run from the USB stick?