BEAGEBOARD: Yes it is an opensource hardware initiative by beagleboard.org. A small board at the size of your palm packed with ARM cortex A8 @ 1GHz, USB hosts to connect to keyboard mouse..etc, 10/100 Ethernet Port, 512 MB LPDDR (Low Power DDR) RAM, it also has a DIV-D port to connect to a monitor, Stereo IN/OUT for audio in/out, it also has a camera extension header. it is available at 149 dollars. Check out the following video:
here is the Beagleboard xM link http://beagleboard.org/hardware-xM their description clearly mentions that this board can be used for DEVELOPMENT purposes.
PANDABOARD: There is also a equally competing Board called Pandaboard (http://www.pandaboard.org/) with a better processor Dual Core ARM Cortex A9 @ 1GHz, Bluetooth, WiFi options, DVI-D Connector, HDMI v1.3 connector, 10/100 Ethernet, Camera extension header, 1GB LPDDR2 RAM, Audio in/out and also comes with status LED’s. it is available on their website at 174 dollars. Looks to me like pandaboard is much more powerful than the beagleboard. Check out the unboxing video of pandaboard:
One more disadvantage as you see in the above video is that you need to buy all the connection cords, nothing comes with the board. It is just the board, so do consider the other cost.
Here is another video showing the booting with pandroid OS on the pandaboard: