ioioio, roaming can be trivial, if the right setup is done. I know of plenty of people who've made seamless roaming wireless networks using the "dumb node" system. The trick is the range of the transmitter. And right now, for private and in building corporate use, B and G are plenty. But for what is being considered here, nothing less than 2x Wireless N will do. If it doesn't have the range, it won't work as intended. That's why 3G towers are so strong. To be practical, each of your towers would need a 15-20 mile range, at the minimum. In higher density areas, 1-2 miles would be plenty. But that's still a ton farther than the couple hundred feet of Wireless G right now, or few thousand of Wireless N.