I have to eventually make it out to MASS MoCA before 2033 to see the spectacular Sol LeWitt retrospective. After enough time spent procrastinating on the interactive floorplan I have deemed this piece my favorite.
It was first exhibited in 1995 at the Mead Art Museum, where four college sculpture students executed it. The piece calls for the first drafter to take a black marker and draw out an irregular, hilly line at the top of the piece. The next person uses a red marker to trace directly below that line, but without ever touching it. Then a third person with a yellow marker does the same, and the fourth with blue. This repeats until the piece reaches the bottom. The lines can never touch. Read more about it here. and maybe even make your own.