BeagleBone is open hardware platform in line with BeagleBoard having AM3358 microprocessor based on ARM Cortex-A8 core. Design of BeagleBone is done with approach of supporting CAPS. CAPS are add-on boards which can be develop over a period of time as per additional peripheral requirement. This is pretty much in line with Arduino‘s shield concept. Priced at 89 USD, it’s quite affordable with the kind of features it is providing. But it misses on board display support such as VGA, DVI-D or HDMI.
Design material (Schematic, Gerber, BoM etc) for BeagleBone are available here.