If you're looking for a more permanent use for a Raspberry Pi, one useful example has been created by Instructables member Aleator777 - a simple device that alerts you to new Google-hosted email. The Pi runs python code that checks for new email over regular periods, and then triggers a GPIO pin which in turn controls an N-MOSFET which illuminates LEDs. However thanks to the code you could control all manner of things - lights, sound, relays and more. A quick demonstration is shown in the following video:
You can find all the details, code and the files for the enclosure in the project Instructable page. And for more, we're on facebook, Google+, and twitter - so follow us for news and product updates as well.
If you're looking for a more permanent way to mount circuitry to your Raspberry Pi, check out our new PiBreak - the prototyping board for the Raspberry Pi. It provides labelled breakout pins for all GPIOs, a large prototyping area with solder pads, and power rails for easy power connection:
Furthermore the PiBreak also includes mounting hardware to firmly attach it to your Raspberry Pi using a nut, bolt, and spacer - and is compatible with all revisions of both model A and B Raspberry Pi computers. For more information about our new PiBreak board, our Getting Started guide, and to order - visit the product page.