Geocachers use a wide variety of software in pursuing their sport. This includes programs for mapping, managing their waypoints, and other uses.
A handy program to have on a laptop, especially when doing paperless caching. You can load up all the area caches, plug in your GPSr and autoroute your way from cache to cache. The one big disadvantage is that it cannot directly import GPX or LOC files. You need to use a separate program to convert the waypoints to a CSV file. Streets and Trips also allows you to create custom icons for all your waypoints, so for example, you could load in all your caches by type and give different icons to the traditionals, multis, virtuals, etc. Streets and Trips is Windows-only, and can be found cheap at Sam's Club.