Tableau Public is a general-purpose tool with a lot of capabilities. It's more powerful than Many Eyes but also has a significantly steeper learning curve. ou can use it to put together single visualizations or dashboards with multiple visualizations that can be filtered in unison.
If you're using the free Tableau Public service, everything is hosted on its servers. Once your visualization is published, anyone can download your data and workbook structure. There is a paid version that offers more features and the ability to keep your workbook and data private.
Windows-only Tableau Public desktop software is required to create visualizations; visualizations can be viewed on any OS with a modern browser.
Find it at: http://www.tableausoftware.com/public