An unlimited, contract-free smartphone plan for $19 a month? Sounds too good to be true, but that's the promise from Republic Wireless, a new hybrid cellular/VoIP carrier from Bandwidth.com. You dish out $199 for an LG Optimus S Android phone upfront (the only model offered on the network right now), then sign up for its cheap monthly service. In return, Republic Wireless gives you an all-you-can-eat buffet of unlimited calls, texts and data. The catch? Republic Wireless assumes you'll be connected to a Wi-Fi network for most of the day, only using a cell network as backup. The service is still in beta (and trial slots are currently full), but Republic Wireless will supposedly let folks in by mid-2012. When it does, should you sign up for this ultra-low rate? Read on.