The Boarduino is basically like an Arduino. By default it comes with a chip preprogrammed with the Arduino bootloader (also known as an STK500v1bootloader) but you can use it as a general purpose AVR module
The Boarduino is designed to be inserted into a solderless breadboard, any standard breadboard will be suitable. Simply insert into the breadboard, making sure that the header pins are straight so that they can be easily inserted.
To remove, grab both ends of the board and gently rock back and forth. This will keep the header pins from bending.
The easiest way to start loading Arduino sketches into the DC Boarduino is to use a FTDI USB cable. These cables have the USB chip inside the cable and a 6-pin socket on the end.
This socket plugs into the Boarduino as shown, and then you can simply plug the USB A connector into your computer. Use the same drivers that you would use with a normal Arduino.
Connecting a FTDI breakout board is easy, wire up 5V and ground so that they are shared with the boarduino, then connect tx and rx. If you are planning to use the 'auto-reset' capability, you will need to place a capacitor (.1uF is just fine) between the DTR line and the reset pin. For the FTDI cable connector, this capacitor is on the board but since there may be situations where the reset line for the microcontroller needs to be connected straight to TTL logic, there is no capacitor on the reset pin.
The bootloader installed is a cross between the NG and Diecimila. There is a 7-second timeout after pressing the reset button but once a sketch is uploaded it starts immediately.
If you'd like to have the auto-reset capability, make sure C6 is soldered in. With Mac's and Linux it should just work fine.
If you're using Windows you'll need to make a slight change to the driver preferences. In the Device Manager, select the USB COM port
Then right click and select Properties
Click on the Port Settings tab, and click on Advanced...
Make sure Set RTS On Close is selected.
Note that, sadly, the Boarduino will not automatically start the sketch after upload if you do this. Its a bit of a tradeoff and you may find that pressing the reset button is faster and getting auto-start is better for you.
There is also a standard 6-pin ICSP (In-Circuit Serial Programming) cable that can be used to burn a new bootloader or just reprogram the chip.
If you are planning to draw a lot of power from the 5V regulator, say for servos or many LEDs, you may want to add a heatsink to the 7805. Just bend the regulator back a bit and slip one on.