Quip: http://www.softwareag.com/developer/quip/
Quilt: http://www.almaden.ibm.com/cs/people/chamberlin/quilt.html
Kweelt: http://db.cis.upenn.edu/Kweelt/
Tamino: http://www.softwareag.com/tamino/
Ipedo: http://www.ipedo.com/