You’ll always have a pen and a stylus ready for action with the Niteize Inka Mobile Pen + Stylus. This dual ended writing instrument features a nylon and carbon fiber body with a carabiner clip on one end. One end has a capacitive stylus tip and the opposite end has a blue ballpoint pen. But it’s no ordinary pen, it can write upside down, in extreme temperatures and even underwater. Refills are available separately. Both ends have see-thru caps that protect and allow you to see which end is which. Available in black, blue and green, the Inka Mobile + Stylus is priced at $11.99 through Niteize or for a couple dollars cheaper through Amazon.