We can use them to cut things, create laser light shows, and also as a rangefinder.[Ignas] wrote in to tell us about [Berryjam’s] AMAZING write-up on creating an Arduino based laser rangefinder.

In this particular case, it’s a DIY USB polygraph-like machine by [Juangg] using an Arduino and sensors on ... complete with 3D printed enclosure and sensor elements. The polygraph may have ...