Ever been confronted with the problem, that you have a nice OpenLayers client but no way to visualize datasets besides the already listed?
The 52°North OpenLayers extensions allows now the dynmically visualizing of OGC WFS datasets. Try a live demo here:
http://giv-wps.uni-muenster.de:8080/OL/
You can simply add a WFS URL and select the FeatureType to be displayed. Besides, with the WPS extension in the same client, you can also process the data.
This a major step forward towards a real WEB GIS.