The Rasberry Pi is a computer on a single circuit board that packs 256 MiB of RAM, a SD card slot offering up to 16 GiB of storage space and a HDMI port allowing a Linux operating system to run on a simple tiny computer. The computer on a chip has an ARM1176JZF-S 700 MHz processor, and a VideoCore IV GPU. Such a small computer would be very handy as a portable machine that could perform computations on the run as well as powering a robot. The main OS that has been released for the Rasberry Pi is based on Debian Squeeze, with the fast Lxde desktop and the lightweight Midori browser. You should be able to get virtually any distribution working on the Rasberry Pi, but it would have to be lightweight enough to run fast on the Pi. Fluxbox & Tint2 would be even better as a desktop. You would not be running Gnome 3 or Unity on this, but it would be a very cool minicomputer.
The old minicomputers were not as fast as the Rasberry Pi and the first one cost $50,000 to purchase. There is a list of ancient minicomputers in the past that were the first precursors of the modern desktop computers that we use today. But the technology available back then did not allow the miniaturization of components that allows the small size of the Rasberry Pi computer on a single small circuit board and enabling a computer to fit in a very small space that was not possible before. And running Linux as well. With the ARM support that is available for the Linux kernel, it is now possible to add support to the kernel and compile a kernel for the ARM architecture. There is a tutorial here on compiling a Linux kernel for ARM. http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.faqs/ka4134.html. Could these be used to construct cheap computers for the developing world?