Go outside without a spacesuit. Technically you could do that, if you outsmart all other astronauts, only to find out you will suffocate in about 25 seconds, loose consciousness and never wake up.

See the stars flicker. Stars don't flicker, it only seems they do because of the Earth's atmosphere.

Use pens. You probably heard about how Russia used pencils in space while Americans made a special pen for billions of dollars? That is not true. First of all Russians used specially created pencils and Americans simply used markers, so it was the other way around. A special pen was developed but by an inventor Paul Fisher. You know why pens were bad in space? Mostly cause the lack of gravity made the writing smudgy and illegible.

You can't boil water. Well, you can but not like you do on Earth. If you tried only the bottom part of the water would be boiling while the top remained cold. Astronauts have special Space Kettles.

You can't keep track of time. If you try to ask people on a Space Station what time it is their time would differ a couple of seconds from yours. Because of different gravity and the speed in which the Space Station moves their time moves slower.

You can't use perfume. In space your sense of taste is weaker and sense of smell is stronger, so any awful smell will be multiplied and result in a black eye of anyone who uses trashy cologne.

You can't skip physical training. With no gravity your muscles get weaker, many astronauts are almost to weak to walk after they get back to gravity; many of them have weaker bones because of prolonged time spent in zero gravity.

You can't sneeze. Physically you can, but it's highly recommended you avoid sneezing. Not only your gems would floating be all over the Station, but you would rapidly fly away in the opposite direction, sort of like a recoil of a gun.

You can't see a "dancing" flame. On Earth a burning match looks like on the left pic, but in a Space Station it looks like one on the right. Without gravity the hot air won't elevate, also the flame would burn out very quickly. See you next time Space Cowboy.