I'm writing a jQuery application to allow analysis of data with the help of visual cues. My data is retrieved via XMLHttpRequest in the form of JSON. The visual cues include histograms, spark lines, and various other graph types. The idea is that the user is able to narrow their data via these various visual views. My question is thus - aside from the Google Charts API, does there exist a JavaScript way of presenting a Venn Diagram? Requirement: no Flash. Canvas is acceptable.