With the advent of USB3.0 5Gbps thumb drives, it now makes sense to install Ubuntu onto a USB stick and carry it with you. This is different from putting a live CD install onto a stick, this is actually installing the OS to the stick as if it were a hard drive, and expecting the computer to not be slow as a pig. Files and settings are all preserved from boot to boot and you can plug it into most computers you encounter and have your stuff with you.
This is valuable to me on business travel. My company locks down our PCs hard and fills them with corporate spyware. If I want to do personal business, side business or coding in my spare time I don't want to do it on my work laptop.
However to make this work, there are a couple requirements
Need a windows FAT32 partition that is readable by both windows and linux boot. This is so I can transfer files back and forth when the host machine is booted in windows. Windows can't read linux file systems.
Linux files should be encrypted so that if I lose the stick, all my personal information is not at risk
This is the USB3.0 stick that I bought. 32Gb is more than enough to have a 16G FAT32 partition for general use and 16G for Ubuntu apps and OS.
Downloaded the Ubuntu Live CD install .iso
Burned it on a regular 4GB USB2.0 stick, since my computer doesn't have a CD drive using http://www.isotousb.com/
Booted the computer from the install USB. This requires pressing F11 on my Sony VAIO laptop
Inserted the USB stick and used gpart to partition as follows
First 16GB as FAT32 for windows
Next 2GB as linux-swap
Final 14GB as /ext2
When installing Ubuntu 12 pick "something else" when it asks where to install it. Chose the USB drive, in my machine it was /sdc. Name the /ext2 partition / and the linux-swap partition swap
Shut down and remove the USB stick with the install .iso on it, and put in only the new USB3.0 stick. Boot and press F11.
Ba da bing. Comes up in Ubuntu with a handy USB stick drive to put files on that a windows machine will be able to see.