A twist on the hidden ball trick...
B1 reaches 1B. The ball remains live as the pitcher and first-baseman confer. The first-baseman goes to the mound and positions himself astride the pitcher's plate, intending to fool the runner that the pitcher is astride the pitcher's plate. The real pitcher, with the ball hidden in his glove, walks to 1B and pretends to be the first-baseman. B1 steps off 1B and is tagged by F1. Balk? Out? "Time! Don't do that again!"?
F1 and F3 are identical twins.