Reminds me of making my TI-83 draw a bunch of patterns in high school with TI-BASIC. It had functions to lines, circles, and some others. Some pretty interesting shapes emerged from just trying out various combinations of LINE TAN(X),SIN(X),COS(X),ABS(X) and such, with X being a variable that I'd make the main loop increment between 0 and 359, or sometimes multiple variables, or it being incremented differently than linearly. I wish I'd have cataloged them.