You can legit earn money taking surveys online through places such as Inboxdollars but it would be really hard to make a complete living just taking surveys.
I earn an extra $100.00 per month taking online Surveys which pays for my electric bill and I take the surveys in my spare time or while in waiting rooms of doctors etc.
I'd be doing nothing sitting there anyway so taking the surveys gives me something to do and I get $100.00 for doing the surveys.
Most people give up on taking surveys before they reach the payout because it's not very easy to do but you can make some extra money taking surveys.