Using our great KitTen Arduino-compatible board kit as a base, the people from MicroEd Computers have created a nifty little persistence-of-vision display that doesn't require any mad hand-waving. Instead, the LEDs are fitted a small board which is mounted on a motor which rotates them to create the desire effect. For example:
This is a great adaption of POV systems, and could be used as a decoration, part of a store window display, or another random style of data output. To get started with your own, visit the project page for all details and code here. And we're on twitter, so follow us for news and product updates as well.
Although you can use almost any Arduino-compatible board for this project, for a more permanent installation consider using the Freetronics LeoStick. Apart from being one of the smallest Arduino-compatibles on the market with USB, it also has an onboard RGB LED and piezo for sound and knock detection: