GPS has come a long way in the last few years. I can remember the first GPS I ever saw. It was an old Honeywell GPS in a Navajo back in 1992. I was impressed, that unit could display your lat and long in near real time. By todays standards, that device would be considered useless. You still needed a map!
One of my favorite innovations in aviation GPS is the handheld that can be taken out of the plane and used in the car. My store carries the AvMap GeoPilot II Plus which is just such a unit. The unit is provided with a Jeppesen database for navigation in the air and a Tel Atlas database for the car. The GeoPilot II Plus was born for aviation but has all of the features you'd expect in a good street GPS, such as voice driving directions. My one gripe is that it does not have a touch screen. But, I am not sure I would want a touch screen on a bumpy day in the airplane.
To find out more about the AvMap line of GPS, you can visit my store at the link below:
http://www.aviationlogs.com/PilotShop/avmap.asp?cat=45If you just want to compare GPS models, AOPA provides this handy guide.
http://www.aopa.org/pilot/handheldGPS.pdfFinally, AOPA's air safety foundation has a nifty course to help you get more than "Direct To" functions from your GPS (though you don't have to be a member, and the course is free, they do require you to sign up):
https://www.aopa.org/asf/osc/loginform.cfm?course=gps_vfr&project_code=&
