What do you get when two YouTube science nerds decide to make the world’s largest computer mouse? A yellow electric car from the 1980s on the world’s largest mousepad, an empty parking lot.

You may remember YouTuber Simone Giertz for her “sh**ty robots”, including an alarm clock that slaps you awake and a disastrous baby-carrying drone. In her latest project, at the suggestion of a viewer, she collaborated with another YouTuber, William Osman, to turn her car “Cheese Louise” into a giant cursor (video above).

The idea might sound as easy as attaching a mouse to the vehicle, but it wasn’t so simple. As Osman explained the process in his post-project analysis, an optical mouse only works when it’s about 1 mm away from the ground, and since the car can’t move sideways, it only sees forward or backward moment. The duo thus had to replace the optical lens in the mouse with a tiny camera lens, and use a magnetometer to determine the direction in which the car was moving. For a more thorough explanation of the technicalities, you can refer to his video on the project, below.

So with a bunch of tinkering, and by using the horn as the mouse click, the two managed to make the make the world’s most impractical, yet entertaining, computer mouse with Giertz’s yellow Comuta-Car.

The result? They managed to draw something vaguely resembling a yellow triangle.