In as much as my main business is geospatial services I do the following.
Idaho has a fairly useful database of land use graphics in ESRI shape file format.
I down load those files from the State then extract the important/useful stuff into my hunting folder.
I then use MapInfo (GIS software) to convert to MapInfo compatible files then overlay on aerial images of the area. I then have a set of two year old aerial images with topography and overlayed with land use boundaries. Nifty for doing "office scouting".
I then convert the MapInfo files back to ESRI shape files to load onto the IPaq for use with field software on the Ipaq.
I have the Ipaq w/software both GIS and Exbal and a blue tooth WAAS corrected GPS receiver velcro'd to my almost camo hat or shoulder.
Thus I know precisely where I am when I'm lost.