Aliens did not do it 3 cm round badge

This keychain has a prohibitory traffic sign with a cartoonish flying saucer and a stylised pyramid on a white background, crossed by a red "forbidden" line. The sentence "aliens did not do it" in capital black letters runs all around the sign on a light green background. As an archaeologist, you will probably have had to deal at least once with a friend or relative asking you about the latest breaking scoop they heard on History Channel. There is always someone wondering how ancient egyptian pyramids were built (no matter how many times you tried to explain)... and the obvious conclusion is that it must have been aliens. When they reach that conclusion, stab them with the pin of this button. Or, you know, just threaten them with it.