"צביעה באוכלים" (coloring in foods) - the stringent view of some poskim
Automatic Toilet Flushers, Automatic Sinks, Soap Dispensers, Doors, etc.
Is One Allowed to Prepare from One Shabbos to the Next Shabbos?;
removing the thin piece of silver-foil or plastic which is on top of a yogurt, leben, coffee jar, etc.