"Lost dollar bill. If found please return to..." Earl Vickers has, apparently for years, been doing rubber-stamp conceptual art projects with US currency. This one asks people to return a lost bill with a given serial number; some people have actually done it, looking to get a reward. Also: Among the other oddities on Vickers site is "Things Other People Accomplished When They Were Your Age." By my age, "Matthias Jakob Schleiden, a German botanist, formulated the cell theory of physiology."