Nem's Tools
GCFScape
FreePowerful archive extractor for Valve packages
Windows
MAP Viewer
FreeView .MAP files in different modes.
WindowsTerrain Generator
FreeGenerate terrain with complete 3D control.
WindowsBatch Compiler
FreeCompile all your maps easily.
WindowsCrafty
FreeBrowse 3D objects, material, model and files.
Windows
VTFLib
FreeHave a library for LGPL open source programming.
Windows