is an experimental web application by Google, which allows you to gather, visualise and share large sets of data.
Facing an overwhelming data table? Fusion Tables are there to help. This web app allows you to upload your spreadsheet or CVS and KML files and to visualise them instantly, as a map or chart. You can then easily share and publish this visualisation.
Your data can then be shared and merged with those of others, if you see that other users are working on similar sets. Everything is synchronised, so you can be sure they are always up-to-date and comprehensive.
Need data? Google offers a search engine allowing you to browse data tables. Enter your keywords and see what has already been made public. The data tables you find from Google can be directly imported to Fusion Tables.
Don't forget that even if you choose to keep it private, once your data is online it is no longer secure. Have a look atto learn more about securing your data.