I'm looking for a survey tool that will only allow one response per person yet still guarantee anonymity.
As far as I can tell in Google Forms, there's no way to ensure that each respondent only answers the survey once.
SurveyMonkey's email collector allows you to send a unique link to each email, yet it also allows you to track responses by email -- thus negating the anonymity.
Educational Technology Specialist
Main Street Middle School
170 Main Street
Montpelier, VT 05602
President, Vermont School Library Association
The Vermont Library Conference May 12 & 13, 2009