Siemens showed a communicator "badge" at CeBIT that recognizes voice commands and can be used to place or receive phone calls and potentially control other devices (picture here). Like Vocera, this hands free communications device uses an extensive voice recognition vocabulary to execute various commands via a combined system of badges and a server.  Unlike Vocera, this device is not released, has no text messaging capability, and requires an infrastructure that is nonexistant in hospitals -- Bluetooth.  You can get a bit more info here.