Firebird is a relational database offering many ANSI SQL-99 features
that runs on Linux, Windows, and a variety of Unix platforms.  Firebird
offers excellent concurrency, high performance, and powerful language
support for stored procedures and triggers.  It has been used in
production systems, under a variety of names since 1981.

For more information on Firebird and InterBase, see:

WWW: http://sourceforge.net/projects/firebird/
WWW: http://www.ibphoenix.com/
WWW: http://www.interbase2000.org/
WWW: http://www.interbase.com/
WWW: http://www.firebirdsql.org/