Share GPS

Franson GpsGate	Run many GPS applications using one GPS, share over networks, log data, simulator, connect to GpsGate Server and much more.
com0com	Allows creation of an unlimited number of virtual com port pairs. Also the home of com2tcp, which allows redirection of a tcp port to a virtual com port.
Android SDK	The android SDK contains the adb tool, which is necessary for TCP port fowarding when connecting over USB. There are also stand-alone versions of adb out there, try searching.