Sometimes 3DS accessories are useless pieces of plastic tat, but occasionally they're practical and stylish. We doubt this one qualifies for the latter description, but you can decide for yourself: behold, The Germa Roller Touch Pen.
We think the picture says it all, but here are some details. The face roller on the end of the stylus uses germanium, and like most beauty products with a silly name it's supposed to have healing abilities that give you smoother, more beautiful skin. These rollers are apparently quite common in Japan, but new breakthroughs in science — or a marketing bright-spark — have made it possible to combine this concept with a stylus.
So, if you're concerned about your skin while playing a game this could be the answer, and the advert suggests it'll make you better at identifying natural objects, too. If you do live in Japan you can pick up a grey, black, or pink model for just ¥1,480, which is a little under $20.