Extjs based online Spreadsheet/Excel

After a while, extjs based online Spreadsheet/excel is released. You can view the demo @

www.feyasoft.com -> My Document -> Right Click Mouse(New Spreadsheet)

Currently it has the following features available:

1: Increase columns by auto scroll down the mouse
2: Cut/Copy/Paste
3: Undo/Redo
4: Add/edit/delete comments
5: Save As

There are several features on the list for process:

1: Calculate (Summary, Average, Min, Max etc)
2: Export as Excel/CSV