Watching Deb doing her Mary Kay make-up party on Saturday, I couldn't help but wonder if there's a more precise way to match a foundation colour to a face. I imagine a spectrometer to measure the skin tone exactly and some simple software to suggest a match. Better yet, it would be possible to mix a tone specifically matched for a particular face. This would all have to be packaged appropriately for a beauty consultant, though. If it starts looking like the paint mixer down at the hardware store, I think it would lose its appeal, even if the results are the same.
Mokalus of Borg
PS - Wikipedia article on specrometers.
PPS - It doesn't mention paint or make-up.