From Andrew Whaley:
Trailgauge is a 3D mapping application with full GPS support. Supports hundreds of map formats from around the world, allowing you to scan your paper maps or use Internet map images. It will automatically download USGS topo maps and aerial photographs and high resolution NASA height data. Add relief shading or contour lines to existing maps. Alternatively, generate your own copyright free topography maps directly from the height data. Plan and measure your routes and set waypoints from the map. Predicts route times for walking, running and cycling using elevation information. Fly-through your routes in a virtual 3D landscape created from the map or just explore at random. Analyze your tracklogs to extract a speed graph showing mile or km split times. Publish your routes to the Web.
Version 3.0.5 fixes SRTM download failure.