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.

He has a very nice $290 laser particle counter, but was really curious how the $12 sharp sensor he found would stack up. To find out, he plugged it into an arduino and started logging both on pachube.