The DCDC1 is useful when negative or bi-polar voltages need to be generated. Also, it can supply isolated power for your low level electronics when the main power is noisy (think automotive). It can be used to generate higher or lower voltages but there are step up and step down boards that are less expensive.
The board is sold as a bare board with instructions since the number of possible variations is > 50. Click on the instructions link below for parts list, build, and configuration information.
Click here to see some built example boards.
Instructions Link
For the moment sales are thru ebay. Click here for ebay link.