Building a Hacker's Deck

Everyone seems to have a pretty definite opinion on the choice between Desktop or Laptop. I've fallen into the former category mostly due to my love of screen realestate. However, I tend to participate in a fair number of hackathons, code-jams, and the like, the usual protocol is either alone in my room, or lugging my not-so-dainty system around.

My experience with doing development in a laptop has not been great. A combination of being incredibly picky over interface devices, and being incredibly used to 2.5 screens (I have a small 10 inch screen complementing my duals), I found the process cramped and over all unsatisfactory.

Enter the Mobile Desktop.

I've been dying to design and build something in the middle. A computer which is portable, but it's design isn't bound to certain keyboards and screens. Here's my wish list:

• Small form factor. Something approaching the Asus EeeBox
• Hard drive space is largely irrelevant. Anything over 30 gigs should be good
• Lots of RAM. At least 4gig, hoping for 8gig
• At least a Dual Core 2.5ghz
• 4 USB ports, but something in the realm of 6-8 would be fantastic
• I would like to have support for two screens, but I think that's a pipe dream
• Integrated Wireless would be nice, but I have a nexus1 for that;)
• Lastly, I want to integrate a small battery into the device. Something allowing for 20-60minutes of run time. This will allow me to move the device around without worry of it turning off. This might be tricky, but really worth the extra effort.
• Budget? Under $500

My two approaches I'm thinking of is either buying an EeeBox, gutting it, and adding on the additional parts. The second approach is to simple build it from scratch. This is more favorable simply because I can avoid the Atom processor which is meant for long battery life, which I have no need for. However obtaining a good case to fit this weird computer might be tricky.

If you have any tips or part suggestions, I 'm all ears!