Contouring

Map Maker Gratis				3.80 Mb
Model and animate terrain from point, line, or surface data. Delineate watersheds, line of sight, render forests and water. Use data including USGS, Shuttle Radar Topography, Surfer, ArcGrid, and Idrisi32, and more
3DSM				319 Kb
AutoCAD R12, R13 Add-on for Terrain Modelling
DEM3d_100				2.1 MB
DEM3d Viewer version 1.0 from the USGS
dXmPlus
dXm is for 32 bit windows and is easy to use. It triangulates 5,000 points in less than 1 minute on a PII processor running at 500MHz. It can save contours to a DXF file to be imported into AutoCAD or other CAD software. dXmPlus created contours and cross sections from a triangular mesh. Contours can be exported to a DXF file, or printed. Data input is via .XYZ, .TXT, .PRN and .CSV files. A fully working copy is available for a 5 day free evaluation
MicroDEM 4.0				Unknown
3D visuallization software from the US Army
Surface III				Unknown
software for creating contour displays of 3-D surfaces
TerraExplorer				Unknown
Explore photo-realistic 3D environments from satellite imagery and photos
Triangulator				n/a
Triangulator is a MapInfo plug-in for creating contour maps
XSect				n/a
XSect is an Av3x extension that displays vertical profiles of point data. This lets you look at your data "from the side" to show how values vary with depth or elevation along transects. It's not free but its cheap!