GeoServer
Home page: http://geoserver.org/
06 Feb 09 -- I decided to take a crack at installing GeoServer 1.7.2 today.
"GeoServer is a Java-based software server that allows users to view and edit geospatial data. Using open standards set forth by the Open Geospatial Consortium (OGC), GeoServer allows for great flexibility in map creation and data sharing."
The crucial bit is that it allows edits. Mapserver does not.
WFS-T comments: http://weblogs.java.net/blog/2006/01/09/geoserver-wfs-t
Sample GeoServer site
The Portland TriMet system map is on GeoServer
This is from the Portland Trimet site... GeoServer, OpenLayers, TileCache, PostgreSQL, PostGIS, GDAL, Extjs, Freemarker, Solr, Antlr, Balance Ant, Http Client, Tomcat, Apache, and Cent OS are the underlying technologies used on this application. We're indebted to the contributors of these (and many other: eclipse, firefox and firebug to name a few) open source projects for sharing their efforts and expertise.