TPoX is an XML database benchmark based on a financial application scenario. It is used to evaluate the performance of XML database systems, focusing on XQuery, SQL/XML, XML storage, XML indexing, XML Schema support, XML updates, and other aspects.
Dungeon2011 is a generic, no-DDL, all-purpose database schema for SQL Server. It is embeddable into database centered software projects and can serve as the base for company information system. The front ends are provided by separate SF projects.
db4o is the world's leading open source object database for Java and .NET. Leverage fast native object persistence, ACID transactions, query-by-example, S.O.D.A object query API, automatic class schema evolution, small size (http://developer.db4o.com)