What is a good simple, preferable open source, reporting tool?

I’m looking for a simple (*easy* to install and use) reporting tool to generate some simple reports. I need the ability to automate report generation and reports will need simple graphics (pie chart, bar graph) and ability to include logo graphics. Open source or free wold be best, but cheap would be ok too as we’re a small biz. Our data is generated on FreeBSD systems and our client machines are all Win XP so probably best if it’s XP based. Thanks.