The small red box to the left of TV is the Raspberry PI. Successfully installed and running Raspbian Wheezy.
I learnt about Raspberry PI from Neo here on unix.com. Thanks to you Neo 
I've been tossing around the idea of picking one of those up lately. Not 100% sure what I'd use it for at the moment.
I do hope for the Raspberry PI to become the breakthrough of Linux in the developing world. The numbers that OLPC are achieving are too small to create that critical mass for global OS diversity.
Been using the Beagleboard, here.
Had mine for months, still in its box. Not even powered it up yet...
I have thought about getting AROS working on it to give the AMIGA feel.
Still using my Arduino Diecimila boards for fun...
You might be interested in the DLP-IO8 or DLP-IO20 boards, you can do arudino-like I/O on any PC or Mac. Each pin is individually controllable between 5V logic in, 5V logic out, or analog in.
I should mention Android phones for users that like their root access.