Alright the usefulness of nuts in physics is questionable. But... there is this cool and interesting experiment where nuts are placed on top of an embroidery hoop that is in turn sitting on top of the mouth of a bottle. By quickly pulling away the loop it is possible for the nuts to fall straight down into the bottle (hint here: think inertia). When you think of it in these terms it is not a stretch at all to use a box of nuts in a physics experiment. Actually students will be thrilled at this challenge. 1/4" hex nuts come in a box of 100. Go nuts with it!