Maarten Balliauw has written up a guide to saving the output of your PHPExcel applications out to the Documents service that Google offers.

As you may know, PHPExcel is built using an extensible model, supporting different input and output formats. The PHPExcel core class library features a spreadsheet engine, which is supported by IReader and IWriter instances used for reading and writing a spreadsheet to/from a file. Currently, PHPExcel supports writers for Excel2007, Excel5 (Excel 97+), CSV, HTML and PDF. Wouldnt it be nice if we could use PHPExcel to store a spreadsheet on Google Documents? Let's combine some technologies.

The two technologies in question are a standard install of the PHPExcel library and the Zend Framework (with its Zend_Gdata component). Using the component, a save() method is created and hooked into the IWriter interface of PHPExcel. When this save method is called, the Zend_Gdata component connects to the Documents service and uploads the resulting information for the account you supply.