I just saw this system at the NADA and was fairly impressed:
http://www.dealerconcepts.com/ It uses those same key tags that you get from the grocery and other stores. People really use them for other markets, so I can't imagine it wouldn't work for dealerships as well. It is probably lower tech than you were looking for with the swipe cards, but last time I looked into those there was huge front costs.
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** Rob, Editor Dealersedge/WD&S **Help is only a message post away!
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