I was reading this thread and decided to make my own version that used the numbers that the Linux counter and Ubuntu counter projects give out.
So, thanks to MenZa for the Idea, here it is:
The barcodes match the user numbers, and the svg has instructions for customizing them.
Print it and stick it to your laptop, desktop, server, toaster, refrigerator, microwave, (etc).--Feel free to include include pictures.
It is licensed under the GPLv3, so if you post a modified version, please give out the svg too.
EDIT:Karmic and Lucid versions are in post #3