I just completed a remote survey from Google for a $75 American Express gift card. While I can’t discuss what it was about (you must sign a non disclosure agreement), I thought others might be interested in participating in these surveys. Mine took about an hour.
You sign up and if they need you for a survey, they will contact you by email with times. You reply back with what times you can do it, they will confirm the time and date and attach a non disclosure form to send back. Pretty basic stuff and the survey is a pretty painless hour.