A Quick Way to Demonstrate Your Age
The following website describes obsolete skills, such as "Cleaning head of a VCR," "Placing a coin on a tonearm to prevent skipping," and "Using a slide rule" that can immediately tell you how old you are. Others are less predictive, such as "Sword fighting" or "Polaroid photography," the latter of which might date you to the era of bell-bottom pants, but actually was only recently discontinued by the Polaroid company. Still others are of an incredibly recent vintage, namely "Assessing the relative merits of BluRay and HD-DVD."
At any rate, enjoy.