I am testing the new Google Spreadsheets as there is a new feature I really need: the 200 sheets limit has been lifted (more info here: https://support.google.com/drive/answ
Here is the solution, just write it like this:
https://docs.google.com/spreadsheets/d/
I know it's weird to write the KEY twice, but it works perfectly. A teammate from work discovered this by opening the excel file in Google Docs, then File -> Download as -> Comma separated values. Then, in the downloads section of the browser appears a link to the CSV file, like this:
https://docs.google.com/spreadsheets/d/