From personal experience, I can recommend Amazon Mechanical Turk as a website where surveys are usually valid. Mechanical Turk allows individuals to complete small and usually easy tasks for tiny amounts of money. Since the tasks are fast, you can complete lots of them in a few hours, and if you're fast the pay can eventually equal a minimum wage job.
Alternatively, the site Swagbucks rewards answering surveys with, well, swagbucks, which you can redeem on various prizes. I recommend these sites as good ways to slowly work towards a prize, but you're not going to become rich off of them. If you don't mind small earnings and enjoy taking surveys, give them a try and see what you think!
I don't know of any reliable places that do it, but I know it is possible. However, I don't recommend it. For eight hours of rigorous work you might make $20. And that's assuming you qualify for enough surveys. Most of them are looking for very specific groups, so you will spend a lot of time trying and failing just to get into one of them.
Vindale Research is valid. Pinecone is also. I've been successful with both. As far as the amount of cash, Vindale has paid me multiple times with real money. I am strategic with what I choose, and as another hubber said, it can equal minimum wage pay or higher if you put your thinking cap on. A benefit of doing the surveys is the understanding it gives about your own thoughts.