DIY shield for Arduino

via Adafruit
$26.40
SKU AF-187

Think you can do better? Design your own shield on the cheap with this DIY parts kit. You get a 3.2" x 2.5" (~ 8.1cm x 6.3cm) single-sided phenolic board with copper solder pads and mounting holes and a extra-special stacky header set. This one has one magical 8-pin header that has been bent so that you can plug it into the 'not-quite-0.1"-spacing" arduino headers

Solder it any which way you want, lots of room for hacking!