You might know the problem that you put laundry in your washing machine or the dryer and forget about it. While the dryer is usually less critical, it’s no fun to leave the laundry in the washing machine for hours.
Nolan Gilley wrote a nice article how to use accelerator sensors to monitor your laundry with Home Assistant. Check it out.
I will further look into this. It would be very cool to use BLE for this and use energy harvesting from the vibrations to power the circuit. But unfortunately piezo elements for energy harvesting are quite expensive.