We all have those gnarly hacks that we still think about years after we first saw them. For serial tipster [Inne], one of those is [Patrick Baudisch]’s soap mouse, which is a DIY device for mousing in mid-air that uses components from off the shelf and around the house.

How does it work? The guts are encased in plastic shaped like a flattened pill, which slips into a fuzzy sock. By squeezing it a bit, the plastic pill rotates, spinning the outward-facing sensor round and round. Although we briefly reported on the soap mouse way back in 2006, we think it deserves to be in the spotlight today, especially since there’s a complete PDF guide to building one that’s optimized for gaming. If you want a regular pointing device instead, the conversion is described within.

[Patrick] uses a CompUSA (RIP) mouse in the guide, but any sufficiently slim and also short mouse should work as long as it has a decently long focal range, which is necessary for the sensor to see the hull. Plenty of travel mice out there should fit the bill.

The hull itself is made from two small (empty) bottles of hand sanitizer, chosen for their size, shape, and clarity of plastic. The outermost housing is a baby sock with a snap sewn on. [Patrick] says moving the sock against the plastic is difficult, and has tried various methods for lubrication, such as a bit of mineral oil inside some plastic bags.

Be sure to check out the video after the break, which does a great job of explaining everything from the various types of interaction to construction in 5½ minutes.

Since 2006, [Patrick] has held workshops where people have built their own soap mice. Have you built one? Let us know in the comments. And don’t forget about the Digi-Key-sponsored Odd Inputs and Peculiar Peripherals contest, which runs through July 4th. Declare your independence from regular keyboards and mice and win big!

Thanks for the tip, [Inne]!