Development kits get smaller and cheaper with offerings like Silicon Laboratories' MCU ToolStik demo kit and USB Radio (see the figure). Both are based on Silicon Labs' 8051 USB chip, which provides a USB-based debugging interface to other chips on the same board. These include other Silicon Labs 8051-based chips like the F300. The USB Radio incorporates the company's radio tuner chip.
The ToolStik costs around $10. It comes with a small CD-ROM with Silicon Labs' integrated development environment (IDE) and configurator along with an assembler, C compiler, and debugger from Keil. Demo software can blink the LEDs inside the unit.