Amazon has just started selling Skype phones that work directly off Wi-Fi. No need for a computer. This can be very useful for schools that require telephones but either don't have telephones in the classrooms or don't know where the staff might be at any given time. This unit allows the staff to be anywhere in reach of a Wi-Fi access point -- including Starbucks -- and be contacted. Calls are free and encrypted for privacy. No worries about students listening in. Voice quality should be excellent within the school's network. Calls to real telephones can be accomplished via Skype's Skype Out service. This service does require some payment.
The price of these units will certainly come down as vendors ramp up production. This system can also be used by PDA's with wireless access capabilities. So, if you already have PDAs for some other purpose, they could be the least expensive route to a mobile internal telephone system.
Amazon.com: Netgear SPH101 Skype Wi-Fi Phone: Electronics: "Amazon.com: Netgear SPH101 Skype Wi-Fi Phone: Electronics"