When I teach the Electronics Measurements class at the TechShop in Austin, I take a lot of pride in showing off the Mixed-Signal Oscilloscope.  We have a Rigol DS1102D as well as a standard DSO.  To help illustrate the power of the combined digital and analog channels, I  created a Mixed Signal Oscilloscope Demo Board, based on a counter,  that has an issue that could be turned on or off.  This board is also my first time making use of OSH Park’s PCB service.