Adding beautiful charts to your site does not have to require a hefty server-side process or a third party service. With CSS and a little ingenuity, you can have the lightweight, easy to create visualizations of your data.
The design mavens over at Six Revisions have put together eight examples of CSS charts and graphs. Each one uses little to no images to create snappy bar and column chart. There's even a scatter plot example and some standards-supporting, accessible sparklines.
Google's Chart API is an alternative to rolling your own. Passing your data is almost as easy because it goes in an image URL. While you don't have to pay for the bandwidth of the chart, the API still comes with some strings attached and Google can pull the plug whenever it wants. If you're looking for 3-D or pie charts, the sort of stuff that can't be done with CSS, that may still be your best bet.
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