pOWL " * POWL supports viewing, editing of RDFS/OWL ontologies of arbitrary size. It is even quite fast with the largest available models (e.g. NCI Cancer Ontology containing about 28,000 classes).
* Sophisticated widgets for data editing such as widgets for editing HTML in a WYSIWIG manner or for dates are integrated.
* Questioning the knowledge base. pOWL currently offers an RDQL query builder as well as a full-text search for literals and resources.
* Plugin concept. POWL is easy extensible, unfortunately still laking exhaustive documentation on this - please have a look at the source code and pester the developers. :-)
* Powerful object oriented API. All functionality is accessible by a clean application programming interface.
* Authentification scheme. Fine grained exposition of features and model data: Privileges (view, edit) for users and groups are planned to be assigned to Models, Classes and Properties.
* Versioning. All edits of a knowledge base may be logged and rolled back (depending on time, user and edit action).
* POWL is fast. Models are stored in database tables and only those parts of the model are loaded into main memory which are actually needed. Thus POWL is scalable and fast.
* Multi language support. POWL comes with English and German translations of the user interface. If you would like to provide a translation please contact us!"
The live demo is well worth a look.