The DISCUS project has always supported that intuition that annotation capabilities are a must for knowledge and information exchange. For instance, imaging that you are analyzing the KeyGraph generated from a particular discussion (here you can find an example). You may want to enrich such graph with your analysis, comments, or related information. Basically, you want to add metadata to the KeyGraph. If such a capability is available, a whole new bunch of information will need to be efficiently stored to allow, not only fast and easy retrieval, but allow analysis of the added metadata. The Kowari project is an Open Source, massively scalable, transaction-safe, purpose-built database for the storage, retrieval and analysis of metadata. It provides a simple query language to interact with the metastore (iTQL). If you are familiar with SQL the resemblance will help you get up to speed very fast. The design is oriented to efficiently manage large volume metadata. Informal tests from Joe Frutelle, a NCSA colleague, have convinced me that this metastore can be the way to go for storing the large volumes of metadata that annotation may produce in DISCUS.