GIS Tools
ArcExplorer
http://www.esri.com/software/arcexplorer/
ArcExplorer is a lightweight GIS data viewer developed by ESRI. This freely available software offers an easy way to perform a variety of basic GIS functions, including display, query, and data retrieval applications. It can be used on its own with local data sets or as a client to Internet data and map servers.
Using ArcExplorer (pdf, 1.2 MB)
ArcReader
http://www.esri.com/software/arcgis/arcreader/index.html
ArcReader is a free, easy-to-use mapping application that allows users to view, explore, and print maps. ArcReader is a great way to deliver interactive mapping capabilities that access a wide variety of dynamic geographic information. Using ArcReader, anyone can view high-quality maps created using the ArcGIS Publisher extension. ArcReader is freely distributable and can be delivered with your data for CD–ROM-based publishing of geographic data.
MapSheets Express v1.3
http://gis.leica-geosystems.com/erdascentral/freedownloadsPVT.asp
MapSheets Express (from ERDAS) is a quick and easy-to-use geographic information viewer and presentation tool provided by Leica Geosystems. MapSheets Express provides capabilities for viewing both geographic images--such as satellite images--and geographic drawings, including line-based map information such as ArcView Shape Files. MapSheets Express works with imagery formats including ERDAS IMAGINE, TIFF, JPEG, MrSID, as well as Imagery Web Sites like TerraServer.
Impervious Surface Analysis Tool (ISAT)
http://www.csc.noaa.gov/crs/cwq/isat.html
The Impervious Surface Analysis Tool (ISAT) is used to calculate the percentage of impervious surface area of user-selected geographic areas (e.g., watersheds, municipalities, subdivisions). The National Oceanic and Atmospheric Administration (NOAA) Coastal Services Center and the University of Connecticut Nonpoint Education for Municipal Officials (NEMO) Program developed this tool for coastal and natural resource managers. ISAT is available as an ArcView® 3.x extension or an ArcView 8.x extension. Outputs include a) a shapefile that includes green, yellow, and red polygons to represent conditions of good, fair, and poor water quality, and b) an attribute table that includes a calculated value for the percent impervious area and total impervious surface area of each selected polygon.
Related Linkshttp://nemo.uconn.edu/impervious_surfaces/index.htm
http://clear.uconn.edu/projects/impervious_surfaces.htm