MyLot is just like a regular discussion board, except it pays you to post discussions and responses to discussions.  With over 170,000 members and hundreds of interest categories, it's easy to find interesting discussions to participate in.  While MyLot doesn't reveal how they calculate earnings, most posts seem to get between 1 and 3 cents depending on quality and relevance.  Payout occurs through PayPal at the end of each month if you have $10.00 or more in your account.

Pickjack is a question/answer trivia website that allows you to earn for posting and answering trivia questions.  How much you earn depends on how well people rate your questions and how many people get your questions right.  You also get paid for your referrals' posting and answering activity.  It's a fun way to pick up some extra change and some extra tidbits of information that you might not have known before!

This is my favorite paid-to-click site.  At YouData, you get paid to give advertisers your time and attention.  You can earn money by clicking on advertisements.  While there are not a high quantity of advertisements offered currently, each advertisement pays roughly from 10 to 25 cents.  Payout occurs automatically each Friday to your PayPal account, and there is no minimum payout.  In addition, you can earn up to $1.00 for each active referral you get.

Hits4Pay is a paid-to-click program.  Each day you get advertisements in your account inbox.  You get paid 2 cents for each advertisement that you click on and view for 30 seconds.  Hits4Pay is also offering a $10.00 bonus for signing up.  In addition, you get 1 cent for each of your referral's clicks and for those that your referrals refer.  Payout occurs through PayPal at the end of the month when your account has $25.00 or more.

ClixSense is a typical paid-to-click program.  You earn money by viewing advertisements for 30 seconds each (you can continue other activities in a different browser tab or window if you don't actually want to stare at the ad for 30 seconds).  Each ad pays from 1 to 3 cents.  There is an option to upgrade to a premium account to receive a wider variety of ads.  ClixSense has a referral program that pays you 1 cent per referral with a regular account and 10 cents per referral with a premium account.  In addition, you also get paid if your referral upgrades to a premium account.