KIDDAILEY  A friend of mine recently introduced me to Firebird, which I learned is essentially just the OpenSource version of InterBase -- something that's been around for more than two decades and is a) extremely lightweight and b) extremely reliable. So reliable in fact that it's often use for embedded systems and the DBMS itself can be slimmed down to a mere 5MB (or so I read). Even still, my full working install has a bin folder of only about 8MB!

I've recently begun experimenting with this and am really surprised. For being such a tiny install, it's packed with speed and many of the same features you see in MSSQL, MySQL and PostgreSQL, but without the cost, bloat and weird syntax.

Full support for stored procedures, functions, domains, triggers, referential integrity, transactions etc. right out of the box. .NET providers and ODBC drivers are available as well as a number of free and commercial GUIs for management. Not to mention that it's available for a myriad of platforms.

If you're starting a small-medium scale project that needs a robust SQL DBMS, this might be worth a look.  
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