Just about everything from metal projects (CNC plasma created) to wooden projects (OF created) and even tech stuff. I wrap the piece in paper first (packing paper sheets from Home Depot) and then lay it into the foam. I do a 3 piece foam sandwich - flat bottom piece, middle layer with a cutout and then a top thin panel. That way I’m not spending a lot of time or making a big mess hogging out the foam. Sometimes I’ll do some small dishing out of the foam in the bottom layer if I need to make room for some 3D projection on the bottom of the piece.