How did the breadboard playing turn out?????
I got this far: ;D
But I did work on my current Arduino project (alternator-driven LED bike headlight). So it was a good weekend. I will be playing around with this soon because said project needs a good PWM to analog conversion as most LED drivers don't take 4-8KHz PWM inputs and 490 Hz is WAY too slow when you're traveling at over 30MPH. It's pretty psychedelic, actually. :o
It just occurred to me that the RC filter could use smaller parts if you use the TCCR stuff http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1235060559/4#4
to bump up the frequency on the PWM output. If it were at one of the really high freqs like 31KHz, you could use a lower value cap and the output ripple would be smaller.