They include sites that seem to be their competitors because they earn referral fees when you buy memberships. A couple mentioned in scam forums even try to dupe you into buying the same list at other membership sites they own under different names. Naturally, these sites also have an incentive to exaggerate how much you'll earn from online paid surveys.
I also have used Synovate Global Opinion Panels, which is now I-Say by Ipsos. They send you surveys pretty frequently and the points you accumulate can turn into actual money! You can receive an actual check from them, or choose to redeem for a gift card. I haven’t cashed out with them since they changed into the new system, just because I’ve really stopped taking the surveys because I’m lazy 🙂 Here’s the link: http://i-say.com/Rewards/RewardsProgram/tabid/203/language/en-US/Default.aspx
Some pay with points that are redeemable for cash or goods and typically you must rack up a bunch to redeem them for anything of significance. Others may give you a gift card, discount, or another token of appreciation for participating. Many others pay nothing or only offer sweepstakes entries for completing screening surveys to determine your eligibility for other, paid surveys. A few don't pay much of anything, unless you recruit others, as in a pyramid scheme.
You won't get rich doing these things but it's legitimate and you'll get paid in the end. For example, you get a penny for each email you click. You get a penny for a video stream. You can earn dollars for fulfilling offers but those aren't nearly as quick as reading an email. They are upfront in what you get paid so you can decide if it's worth it.
Cashback shopping: Who doesn’t love getting cash back? It's a great incentive for shopping because it feels like you're being paid to do so. It's usually best to use the offers only when you were already intending to buy the product. If you love saving money at discount stores or at places that offer cash back, there are a lot of survey sites out there that will open a lot more offers to you. Survey sites can offer cash back because they're paid a portion of the profit for referring you.
Survey Club has been offering online paid surveys since 2005, and in the fast paced every changing world of the web that’s a reassuringly long amount of time. They are a bit of an acquired taste, in that they specialise in long, detailed surveys for high end clients rather than the quick and cheerful consumer surveys that you may be more familiar with. Whilst this does mean that you may have to commit a bit more time, it does mean that if you have the patience to persevere with them they pay more money than most survey and reward sites. They also offer local taste tests (see what I said about ‘an acquired taste’?), and secret shopper opportunities.