I have tried a variety of online survey sites and Opinion Outpost has by far been my favorite. While certainly not a way to get rich, I have found it rewarding to earn a little money, whether in the form of Amazon or Citi gift cards or a check. I normally do these surveys during what would otherwise be down time for me - while the kids are happy playing but still need me to supervise or while watching movies with my family.
Many of the surveys offered for me to try I end up not being able to finish because I do not qualify for some reason. But I am able to complete and be rewarded for enough of them to keep me coming back.
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MySurvey123.com - Opinion Outpost