Cell/pda video quality isn’t good enough for showing sign language, so these University of Washington UI group is working on mobile video capture that specifically picks up ASL signs and then focuses the video quality on the gestures instead of background junk. 
Right now they’re in very early stages, but in a few months they might be on to something…
From the article: “Yesterday T-Mobile became the first major mobile phone carrier in the United States to begin selling service that allows a single handset to communicate over both cellular networks and Wi-Fi hot spots.
The first phones, which are available to consumers in Seattle on a trial basis, link to T-Mobile’s cellular network outdoors and to Wi-Fi routers at homes, in offices and in other locations like airports and hotels. This lets customers avoid using some of their cellular minutes and increases coverage in places where signals are typically weak, like basements and rooms without windows.”