SharpMap is an easy-to-use mapping library for use in web and desktop applications. It provides access to
many types of GIS data, enables
spatial querying of that data, and
renders beautiful maps. The engine is written in C# and based on the .Net 4.0 framework. SharpMap is released under
GNU Lesser General Public License.

New: SharpMap automatic builds, automated tests and more.
Tutorial for beginners If you are new to SharpMap we have added some tutorial-material to get you starting, see the Documentation page or directly:
SharpMap Tutorial
Provider for Esri's File GeodatabaseA new provider has been added to access feature data stored in Esri's File Geodatabase. It is at an early stage and you are invited to test it. It uses Esri's File Geodatabase API SDK, so it is limited to file geodatabases of version 1.2 (created with ArcGIS 10)
Use SqlServer Spatial Objects with SharpMapThe new project SharpMap.SqlServerSpatialObjects offers a converter between SqlGeometry and SharpMap.Geometries. Also included are static classes for SpatialRelation- and SpatialOperation functions.

General interest: a new mailing list for people doing geo-spatial on .net / mono platforms with oss tools
http://lists.osgeo.org/mailman/listinfo/dotnet
Please visit our
SharpMap Supporters page.
Useful External Resources