Conversation

The crossing in front of my flat got this nice #japanese gadget installed.
At day, you see a bit of plastic and solar cells. At night, you see that there is a ring of red led which flash after each other, so looks like a 'light running in circles'. There is a proximity sensor inside, when a car approaching the frequency of the flash gets increased. So, as soon as you see the crossing from far, you can guess from the frequency whether other cars are approaching or not.