On Developer.com today, Jason Gilmore has written up a tutorial that introduces one of the handy features that came with upgrading to PHP5 - SQLite support:

One such solution is SQLite, a fully-featured relational database that, at just 250KB, is by itself able to easily fit on a floppy disk yet is capable of managing terabyte-sized databases. [...] In this tutorial, I'll introduce SQLite, showing you how this database can offer you maximum return with minimal investment.

He introduces the library by showing how it can be used from the command line (along with an example database) and how to turn on support for it in PHP and make queries in the normal SQL syntax.