Ever since I read this certain book about quantum physics, I've thought that electron are creepy. And they are. Reeeeally creepy.
In short, there's this experiment with two slits and if you fire an electron at those slits, it will usually create an interference pattern that suggests that the electron goes through both slits at once. Now, this is slightly creepy, but there is the explanation that the electron acts as a wave which minimises the creepiness as waves are more flowy than particles.
So, the pattern suggests that the electron is going through both slits at once. Now, suppose you want to know for sure and put a sensor on each slit to tell you what's happening while the electron goes through it. That will show you that it's going through both at once, right? Wrong. The electron decides to only go through one slit, and there is no interference pattern created. Electrons seem to be aware that you are watching them.
But wait, it gets better (worse?). Say you turn off the sensor. The interference pattern comes back. Turn it back on and it goes away again. Have it off, fire the electron and then turn it on? No interference pattern. Somehow the electron can tell that you are going to turn it on in the future. IT KNOWS WHAT YOU'RE THINKING!
So yeah. Electron are creepy. Really creepy.