AT&T [T] have launched the Microcell 3G device that aims to give those in bad reception areas a signal to use their phones over a broadband connection.
The 3G Microcell device attaches up to your home router and creates a small femtocell network in your home and routes calls over your broadband connection to AT&T and [...]

AT&T 3G Microcell Home Femtocell Signal Booster Device Launched