Google Fusion Tables :View,merge,discuss,publish and visualize large Excel Spreadsheets on the Web
Google Docs would only allow you to import spreadsheets (or CSV files) that are less than 1 MB in size.But usually excel sheet data that are shared between groups or individuals are much larger than 1 MB.
A very useful Google product Google Fusion Tables allows you view Excel files as large as 100 MB in the browser