There is a lot of buzz out there about this new computer, the gPC available now at Walmart. Arul gives an excellent short intro; however, he missed the fact that this is a Mini-ITX form-factor PC inside of a full-size case (!). You’ll just have to go get your own small-size case (such as some from mini-itx.com).
Wired ran an article on it describing it in full; DesktopLinux.com also had an article on it. The scientific site PhysOrg.com had an article on it as well. There’s other mini-sized computers – from HP and Dell for example – but this is lower in cost, comes with a variant of Linux and it’s available down the street.
The operating system is gOS, a modified version of Ubuntu Linux that leans heavily towards using Google applications wherever possible. There are downloads available of a free version of gOS, but the one on the gPC is optimized for that platform.
Among the stores they listed (for Wisconsin, USA, our area), it says Madison will have it, Monroe will have it, and Milwaukee – but Janesville and Beloit are not listed.
UNIX Administratosphere 
Thanks for pointing out the part I missed – the small motherboard/big size thing. I updated my blog.