I live in a communal house with other students. The fridge setup is a mess. If a family were living in the house, it would be OK, but with four separate individuals, we have four of all the basic goods - milk, eggs, butter - and the fridge is full to the brim. Overflowing even.
We've decided to start sharing these goods, but how exactly? We all use different amounts, and it's hard to keep track of re-stocking.
For now, we just buy in bulk, for non-perishable goods (ketchup), and leave a message on a whiteboard for perishables (milk) so the next person can pick it up at the store. It's a complicated system, and it relies on all of us working together to keep it together. What we really need is a way to automate at least some of the process...
My plan is to build storage units for each good. The unit will have a sensor, typically a scale, to measure how much of the good is used over time. The Arduino 101 will run simple software to track the use, and when it gets low, connect to Amazon's Dash Replinishment Service to order more. What's not available from Amazon, the software will send a text or email, a reminder, to who's next to pick up that good.
A goal for future developement: user recognition. RFID's in bracelets or a camera with face recognition will determine who opened the fridge, so the software can keep track of how much of each product each person uses. Then the good gets reordered, and each housemate only gets charged for what they use.