Alongside the new Brain Age game, Nintendo has revealed a new and innovative accessory for their console: a stylus!
It will retail for 864 JPY in Japan, which is about $9. So it will probably be $9.99 in the US.
It will release on December 27th. In Japan it's available to pre-order in the My Nintendo Store https://store.nintendo.co.jp/item/HAC_A_HEBAA.html