Bushnell's Onix200 comes with a useful set of tools and capabilities including usb connectivity, topo and arial photography maps. It has a black and white display which can be backlit or reversed for night time viewing. The case is rugged and waterprove and fits nicely into the palm of your hand.
I use the unit for geocaching. The chipset and software in this unit is not the most sensitive that can be found. However, it manages to provide accuracy within 20 to 25 feet most of the time. This generally leaves a fairly wide area for a geocacher to search for something that might be as small a fountain pen. This does not necessarily diminish the enjoyment to be had while geocaching since the "hunt" is indeed part of the fun.
As a geocaching and basic navigation tool the Onix200 offers all that is required and then some.