Update: As of October 2012 this is now priced at $12.99.
TI has made it’s $5 alternative to the Raspberry PI available, however to get the special price you need to order soon! Their alternative, the Stellaris board looks interesting enough that I even ordered two as post is included in the price.
The board comes with an ARM Cortex M4F (ARMv7E-M e) architecture along with USB support, the particular chip comes with a built-in floating point processor and DSP instructions. TI also promise that adding peripherals and undertaking a bit if software development will be easy. From what I can see though the board and chipset does not include a graphics processor which in theory could make it less interesting than the PI to many people. That said if you read the TI website they do imply that the chipset is intended more for industrial control applications. TI also offer a number of booster packs that let you add among other things add a capacitive touch sensor, which could be fun for basic sensor applications. The final price will no doubt be a bit higher but for now it is a good deal.