Efficiently dim the car's dome or map light.
http://www.wenzel.com/pdffiles/dimmer.pdf
This converter allows an ordinary AM car radio to receive WWV at 10 MHz. WWV transmits the precise time of day and the car is the most common place to need accurate time.
http://www.wenzel.com/pdffiles/convert.pdf
Tune in WRNO at 15.42 MHz and hear a famous talk show!
http://www.wenzel.com/pdffiles/rushconv.pdf