I have just been alerted to a new service, which lets companies ask very specific questions to targeted demographic groups of people. You can sign up to answer such questions here.
Once you have signed up, you will receive questions by SMS to your phone. You will be paid one dollar for each question you answer, with the money going into your Paypal account.
Since the service is very new, questions are as yet few and far between. The chance of getting a question will also depend on how your demographic data (country of residence, age, gender, occupation, etc) match what the companies are targeting. I have however heard from one person, who has already received payments.
Registration is very fast and simple. After that, you need do nothing at all except wait for the messages to come. So it is a really painless procedure that could put a few dollars into your pocket for practically no effort at all. Why not sign-up now!