As usual the velcro fitted boxes with power from the cigar lighter are leading the way! The only problem being that it is yet another wire to trip over when you get out of the aircraft.
Such a pitty that the autoritys won't enable the TIS system that is avalable in the USA. The system works by data linking ground radar transponder returns via the mode S transponder to the map screen in the GPS.
If this was avalble them the take up of mode S transponders would be much higher because aircraft owners would see some return for fitting the mode S.