Suppose you are on your way to class without any preparation or demonstration equipment or last minute you are assigned to a bare classroom instead of your nice physics room. What can you do to still have a clear and exciting lesson? In this workshop I present a collection of small and quick demonstrations, which require no equipment beyond what is present in a typical lecture room or bare classroom (chalk, chairs, students, books, paper, student bags and typical contents). The nature of the demos is varied, some are to verify an explanation, but most are to illustrate, visualize, or simulate. A few role-plays are included for when students are restless, cold, or sleepy or for when their instructor needs a kick to get into a better mood after a late night of checking students' papers. In the workshop, I will start with a series of examples, but then we will invent our own demonstrations using the objects in the workshop room, in our pockets, and in our bags.