Devices, including Han's (which will be publicly available through the company perspective pixel) use OSC typically implemented over UDP. Most users use VVVV and Java to generate the OSD data from webcams. There is also touchlib, a C++ library for windows.
With Xql in the works, will the multi-touch open source initative catch on in the linux dev world, easily realizing the Han desktop utopia for the end user? And with linux development, will the multi-touch open source translate into increased open source used in embedded systems? The thought of multi-touch devices besides apple's iPhone quickly entering the market via open source initiatives is an invigorating thought, especially if it encourages business to adopt open source practices"