A decorative and functioning Coke machine that fits well in schools or other public buildings.

This Coke machine gives you a potion called "Coca Cola" when you click on "1 Coca Cola", which gives you speed.

Instructions:

First you need any two blocks, which are stacked on top of each other. On the upper block you hang a sign without text. To fill the sign with the text, place a command block in front of the lower block, which you can fill with the command /give @p command_block and fills it with the following command:

/blockdata ~ ~1 ~ {Text1:"{text: "Coca Cola",bold: "true",color:white}",Text2:" ",Text3:" ",Text4:"{text: "1 Coca Cola",color:dark_red,clickEvent:{action: "run_command",value:"/give @p potion 1 12 {CustomPotionEffects:[{Id:1,Amplifier:4,Duration:800}], display:{Name: "Coca Cola"}}"}}

Now you execute the command block, for example by pressing a button, and can remove it again afterwards.
For decoration, you can also attach a frame to the bottom block to represent an output tray.