A powerful, cross platform, SQL database system
Firebird RDBMS offers ANSI SQL features & runs on Linux, Windows & several Unix platforms. Features excellent concurrency & performance & powerful stored procedure & trigger language. WEBSITE link is below, TRACKER is http://tracker.firebirdsql.org
caspin is a thin wrapper library around Mozilla's Tamarin Project, which enables you to seamlessly integrate the AVM2 (Adobe Virtual Machine 2) into your C/C++ Projects.