I hope I haven't committed any serious crime here!
I love my Tom Bihn Brain Cell so much (I have one for my 13" macbook) that I wanted one for my netbook, too. but alas, there isn't one that fits the Asus Eee PC 1005HA.
I looked far and wide, and was unhappy with what I found on the intarwebs, so I decided to take matters into my own hands. I took some measurements and bought a Vertical Brain Cell (Size 1), since it looked to be near exactly twice the size I needed for my netbook. I then proceeded to cleave it in two and repair the appendages to the best of my ability, creating two mini-Brain Cells which fit my Asus Eee perfectly.
I added some pics. Please know that if I've crossed any boundaries as far as mangling a Tom Bihn bag, it was out of my love for the quality of the brand! I was desperate to have a Tom Bihn home for my beloved netbook. :P
Also, I add a caveat that I am an extreme amateur at stitching, especially bags, so please forgive the less-than-perfect handiwork on my part.
Cheers to my fellow Tom Bihn bagfans!