Using bottle caps, boxes, packages with lettering, numbers, or pictures on them.
(Squeezing materials.) how to work with a spill using precut paper towels, napkins, tissues, etc.;
Is There a Problem with Using Foods That Smear When One Is Not Going to Eat Them on Shabbos?;
(Melting ice.) Other types of necessities (in conjunction with putting frozen liquids and warm areas): child, oneg Shabbos, etc.