Google Spreadsheet is a powerful and free tool to manage complex spreadsheets. This tutorial illustrates ten useful formulas you must know to help you simplify the way you work in Google Spreadsheet.

Link:
http://woorkup.com/2010/02/19/…

Check out these posts too:

  1. Google Spreadsheet is on its way
  2. Create a form that stores data in a Google Spreadsheet
  3. Google introduces an Apps tool for sending forms via e-mail
  4. The big Google list
  5. Google Voice for everyone
  6. How Google Works (infographic)
  7. Google Dot Logo