MapServer - a very popular Open Source engine for publishing spatial data and interactive mapping applications to the Web.
GRASS GIS - commonly referred to as GRASS, this is a full featured GIS used for geospatial data management and analysis, image processing, graphics/maps production, spatial modeling, and visualization.
Quantum GIS - commonly referred to as QGIS, this is a user friendly Open Source Geographic Information System (GIS) that runs on Linux, Unix, Mac OSX, and Windows. QGIS supports vector, raster, and database formats, and is often used as the visual front-end for GRASS.
ArcExplorer - ArcGIS Explorer gives you an easy way to explore, visualize, and share GIS information.
The Geomatics Association of Nova Scotia has adopted a tiered level sponsorship program this year. All sponsor levels help generate revenue necessary for the Association to operate but the levels provide different benefits back to the company / organization in return for their contribution. click here for more details on the different GANS sponsor levels.