meanwhile, here's something that caused its fair share of attention. this bmw changes colour! it's a colour changing car! and to do so, it uses e—ink, the same as an e—reader. what we have here is the world's first real colour—changing car. the technology e—ink is amazing. we know it from the e—readers and kindle, it's very low energy, its sunlight readable and it's just colour change, there is no light or led backlight or oleds, it is just colour change. so you just need a little bit of energy to change colour, and absolutely no energy to hold it so it is stable and as an engineer that's a wonderful property to have. the driver can manually choose to change colour, or you can do it via the sensors that are embedded in the vehicle — so you can have a temperature sensor that when it's hot the car will be white, and when it is cold it will be black, or you can have a light sensor