Tools
A repository of available GIS tools. Most should be free.
Hawth's Tools - Spatial Ecology
DNR Garmin - Minnesota DNR
Map Book - Project page
NPS Grid Tools - National Park Service Midwest
Geographic Magnetic Calculator - Resurgenct Software
Home Range Tools - Centre for Northern Forest Ecosystem Research (Ontario)
ET Tools - SpatialTechniques (some free components)
Jenness Enterprises - some free tools for ArcView 3.x and ArcGIS
USDA Service Center Agencies GIS - several ArcGIS tools
Geodesic (True) Distance Tool - USGS Planetary GIS Web Server
CMAP Crime Analysis Spatial Extension - Crime Mapping Analysis Program
Computer-Aided Management of Emergency Operations (CAMEO) - EPA
ARD GIS Tools - NOAA Office of Response and Restoration
GEOTRANS Geographic Translator - National Geospatial-Intelligence Agency
Feel free to email Jason or the listserv about new tools to add. Some of these are standalone tools (GeoMag and GEOTRANS).
MMGUG makes no guarantees or warranties on these tools