UTStarcom UM175 mobile device
Coming to you from one right now. Those Ubuntu folks are really on the ball with mobile! I found this really easy instruction and got connected. Two things that threw me... Network Manager didn't immediately find the device until rebooting, and I had to install it under Windows first to determine its username. I'm somewhat disappointed in the connection speed but I guess that's the trade off for having Internet in very remote locations.
I'm doing this for practical reasons... We have to rethink our way of broadcasting remote sporting events at my radio station. Before, we used a cell connection hooked to a small mixer with microphones and headphones attached. What I'm envisioning now (and so far it appears to be very do-able) is to run an Ubuntu based NetBook with this mobile air device. We'll contact the radio station via Skype giving us much better sound quality than with cellular.
One real big advantage will be the ability for the on site sportscaster to connect to the studio's on-air computer via VNC. That way they'll be able to connect with Skype, put themselves on air, take commercial breaks and close out the event with no board operator needed!
Sometimes I think computers were made for the radio business. :D