Google announced recently a new amazing API go generate charts. Google Charts API allows to create different type of charts on the fly in the PNG-format with the limit of 50,000 queries per day. Currently charts supported include line, bar, pie, venn diagrams and scatter plots. The chart below is generated for example directly using the Google Charts API. Very useful to create charts on the fly and it could be easily integrated with online publishing tools. No need to have GD installed for charts creation, now just read the Charts API documentation and get the PNG anywhere you want.
Sample Google Charts API