Thanks to hackaday.com I learned about a nice promo action at TI. The EKB-UCOS3-EVM - Stellaris Robotic Evaluation Board is a nice toy featuring MicroSD slot, USB host and device connectors, I2C audio with a speaker, ethernet connector (!), 96×6 OLED display, a pair of motors, optosensors and bump detectors, all driven by the LM3S9B92 microcontroller.
This uC is ARM Cortex M3 operating at up to 80 MHz, with 256 kB flash, 96 kB SRAM, a 32-ch DMA, and lots of other shortcuts. It comes with a proprietary RTOS preloaded but the chip is capable of going the opensource way too.
All that for $25 including shipping. Sounded too good to be true, but I ordered nevertheless :-)