Video games can make you laugh or make you cry, but there's only one that can make you smell a batch of freshly popped popcorn. Poptopia is a free-to-play mobile game from popcorn maker Pop Secret, where the goal is to feed kernels to The Almighty Mouth God. But the experience can be augmented with the Pop Dongle: a device that plugs into your phone's headphone jack and emits the buttery scent of popcorn as you play. The dongle has enough smell for between 500 and 1,000 sprays. Unfortunately, while everyone can download and enjoy the game for free, the dongle is much less widely available. The company is putting them up for auction on eBay, with proceeds going to support the American Red Cross — right now the sweet smell of popcorn will cost you more than $100.