"צביעה באוכלים" (coloring in foods) - the stringent view of some poskim
how to Apply the Melacha of 'מכה בפטיש' (Final Action);
Putting the Little Plastic or Rubber Cups on the Bottom of Chairs or Tables and Blowing Bubbles on Shabbos;
How to Work with the Light in the Refrigerator on Shabbos. Part 2;