Google tool for surveys that automatically stores results

I discovered that it is possible to use Google docs to create form-based surveys that automatically write to a Google doc spreasheet:

http://googledocs.blogspot.com/2008/02/stop-sharing-spreadsheets-start.html

This is very useful; I used it to create a simple survey to scheduling a meeting. I found the simple interface easy but also a bit confusing. The "grid" object should be provide some options including one that allow columns to behave like checkboxes instead of radio-buttons.