In my WG, my flatmates and I take turns buying the coffee grounds. Sometimes this becomes confusing, as there are three of us, and the person who is next in line to buy coffee is not necessarily aware that the coffee supply is low.
I'd like to develop a system that ensures that our WG is always supplied with enough coffee. Using Arduino and a photoresistor, I propose to install a sensor inside the coffee ground that will send a reminder SMS to the next person in line as soon as the coffee levels are low.
File:Coffee03.jpg
File:Coffee04.jpg
Above image source: Flickr user iDecrease