What thing/s do you see everyday that reminds you of math?

Question

I have to do a collage that shows things, objects that we use commonly or everyday that uses or reminds us of math. Can you help? I've run out of ideas. I already have Books, road signs, buildings, financial, business, banking, chemistry, science, temperature, computer, clock, game system, internet, music recording systems and TV.

Answer 1

Every object has height and weight therefore it can be reminded of math.  

Answer 2

finding the slope of a flight of stairs.