Enterprise Java Development Tools | SpringSource. I should take a closer look, as it was recently about J2EE and EJB alternatives, and this is one of the more well-known alternatives.
Archive 25. March 2011
Trinity - Microsoft Research. I should take a closer look at this, it sounds somewhat like distributed Redis (in-memory structures that are persisted) combined with a query semantics that is more based on graph relationships (comparable to RDF Triple Stores).