A consortium is working to build an airplane-based cellular picocell technology that supports GSM and Wi-Fi: Cell users with GSM phones would connect via the picocell and calls would be relayed by satellite. Wi-Fi service could also be offered. WirelessCabin (Airbus, Siemens, Ericsson, and others) might have commercial clients by next year.
The Economist notes dubiously: Perhaps aircraft will offer "phoning" and "non-phoning" cabins. Still, what better way to drown out the noise of a screaming baby in the next seat than to phone a friend?