Door scare 2.0
https://www.youtube.com/watch?v=0iwGuMgPJAw
Mumbo Jumbo made this interesting scare machine a long time ago, but it's starting to be well known and people aren't falling for it anymore.
Therefore there is now a variant "2.0".
Simple TNT trap
Everyone can see right off the bat that it's a Redstone chest and that the TNT blows up when you open it....
Fast, simple block exchanger
This simple machine allows you to have a block in your wall replaced after a 1-tick delay.
Simple sugar cane farm
A simple sugar cane farm that can be expanded at will. It works with the observer blocks.
Shulker box exchanger
This quickly designed circuit allows you to swap up to nine shulker boxes with each other, almost without wasting space, to quickly get to different ones of these. This circuit has an automatic reset function.
Item disposal machine
A simple (and actually somewhat useless) machine that quickly helps you get rid of random items. Easily expandable with funnels.
Dimmable light
This automatic dimming light, is perfect for cinemas.
The light is switched off in sequence at the touch of a button, creating a dim light.
The light is switched off in sequence at the touch of a button, creating a dim light. 
