Here's a little something we spotted on Facebook recently.
It's the Firefly Pick, a guitar pick that lights up as you play guitar.
Actually, it's a bit more interesting than that.
Here's some of the literature from its Amazon.com page: (opens in new tab)
"The Firefly Pick allows you to create an LED light show timed to your music. Motion-triggered LED pulses track guitar pick action to add a brilliant visual effect intimately connected to the guitarist's rhythm. The Firefly Pick is the same shape as a normal guitar pick and features a beveled tip optimized by pros, allowing musicians to experience and deliver this brilliant visual effect without compromising the playability or music.
"The Firefly Pick is durable and features a USB-rechargeable lithium ion battery as well as a smart monitoring system that automatically shuts down to save energy during travel. Used by professional performers and beginning students. The Firefly Pick Duo flashes with one color on the upstroke and a second color on the downstroke.
"The Firefly Pick comes in four light motion styles (Classic, Duo, Insanity, and Air) as well as many different LED light colors."