Republic Wireless
Republic Wireless certainly garnered itself a lot of attention with the promise of unlimited everything for only $19 a month and no contract. The company keeps the price so low by using what it calls "hybrid calling" -- a fancy way of saying it relies almost entirely on WiFi and VoIP, only falling back on Sprint frequencies when you wander away from an 802.11 connection. The service may be billed as all-you-can-eat, the reality is a little more complex. While you're free to plow through as much data and as many minutes as you want over WiFi, there are "fair usage" limitations on your cellular footprint. Specifically, if you cross a threshold of 550 minutes, 150 text messages or 300MB of data you may be asked to take your business elsewhere -- not exactly "unlimited" now is it.

Update: Republic Wireless issued a clarification on its Facebook page, explaining that you can in fact go over the 550 minute "example" above.

"People of the republic, we'd just like to clarify that 550 minutes, 150 texts, and 300 MB of data over 3G is just an example, not a limit. The more you offload to Wi-Fi, the more you can use. It's truly unlimited. We do have fair use guidelines and we encourage you to use Wi-Fi whenever possible."

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