The Karma WiFi Hotspot is a "social" 4G hotspot that allows you to openly share your connection with the people around you in order to earn free data (hence the "Karma" in the title). I can see how this would worry people who are sensitive to security issues, but hey, I think it's an interesting idea.

Up to eight devices can connect to the Karma at once, and its rechargeable battery is good for up to eight hours. It's a pay-as-you-go service, meaning there's no provider contract.

The Karma is typically $99 on Amazon, but they're currently out of stock while the old Clearwire 4G service is transitioned over to Sprint's LTE network. Might be worthwhile to add it to your wish list and keep tabs on it for later, anyway.