Within ELCA, EL4J has been used for more than 20 projects so far (the projects were mostly for external clients). The project sizes and domains vary a lot. They include a soft real-time application to supervise vehicles, several administration-support applications of the public and private sector or an user-interface for a bi-temporal database.
There are other uses of EL4J outside of ELCA (mainly initiated via personal contacts). Unfortunately we cannot disclose futher details here.