PhpChart
If you nedd a simple PHP library to build basic charts, check this project. It was created as part of the pgmon project, namely to visualize collected data, but it may be used separately.
This project is hosted on sourceforge.net, on http://timechart.sf.net (or more precisely at http://apps.sourceforge.net/trac/timechart/).
If you need a simple PHP library to draw basic charts, check this project.
