Thanks for the link man! I've only read the Linux from USB hard disk section but I'm afraid that might not work that well for me because it requires me to

a) Disconnect existing hard drives when installing linux to external
b) use the ENTIRE hard disk as a linux partition
c) Switch my boot to boot from USB in the Bios, which I'm not sure if I can do.

But! I haven't read the "install ubuntu onto a flashdrive" part yet. Maybe that might work on the external hdd I have. =D