If you've ever been to CES, you know the pain of limited or no reception in one of the halls. That certainly makes it difficult to communicate with the rest of your team to keep your agendas synced. This is also a common issue at music festivals, camping and more.
goTenna is a product that allows you to communicate in a peer-to-peer method without the need for cellular connectivity. Simply carry a goTenna with you and let it communicate with other users of the device. You can do much of what you can do with a cellular connection, only limited to the broadcast radius of the goTenna and the other users.
goTenna is available now for $199 for a pair.