Fusion Tables is an interesting service launched last year in Google Labs to help users manage large data sets. "Fusion Tables is not a traditional database system focusing on complicated SQL queries and transaction processing. Instead, the focus is on fusing data management and collaboration: merging multiple data sources, discussion of the data, querying, visualization, and Web publishing," explains Google.
Fusion Tables has graduated from Google Labs in September and it will become a Google Docs app. As you can see from the screenshot below, Google Docs includes fusion tables in the list of document types and there's also an icon for fusion tables. Users can already import tables from Google Spreadsheets and sharing works just like in Google Docs.