diddybase - < 1Gb, especially the "test" or "proof of concept" databases, beloved of developers, with less than 10,000 records in each table, or with an entire dataset < available RAM.

terrorbase - Terabytes. Lots of em.

But I agree with Phil, the biggest lack is words for proper OLTP systems with hundreds/thousands of simultaneous processes needing to do non-repudiable, acid-compliant transactions without deadlocking. Think stock exchanges or other trading platforms.