Turkish research and development startup Letvision has built what appears to be a 2013-ish BMW 3 Series coupe that transforms into a 15-foot robot. As an adult whose entire desk is littered with Transformers action figures, I'm sort of freaking out right now.
Letvision started with an actual car for the conversion, so the Letron is a 1:1 scale representation of what an actual robot in disguise would look like. However, the conversion to transforming robot pretty much occupies the much of the vehicle's interior with hardware, so it can only be driven remotely with a Wi-Fi controller.
When in car mode, the Letron can move and turn under its own electric power, but things get interesting when the transformation is triggered. The transformation from car to bot is accomplished with a combination of hydraulics and electric motors and takes just under a minute in the video.
Once transformed, the Letron just sort of stands there and looks around. According to an FAQ on the Letrons site, the bot can't walk, but it can turn its head and move its arms, wrists and fingers. There's also a range of light and sound interactions and an unfortunately positioned fog machine.
Letvision has plans to build more Letrons in the future based on various car models and even hopes that they will one day be drivable in traffic.
Perhaps the weirdest detail is that Letvision will build and sell you a Letron of your own, but only "if the buyers' project and their reasons for use meet the criteria of the Letrons team." Presumably, that means they won't build me an army of evil car-bots armed with flamethrowers.
Pricing for the world's largest action figure has not been stated.