A few months ago I stumbled across 20Cogs, A clever little website that rewards you for participating in various offers, surveys, and tasks.
Sign up to 20Cogs and you will get a free £5 welcome bonus for joining. You then need to work your way through the 20cogs and complete the offers following the instructions carefully to earn your rewards. Some offers are 100% free and don't require a purchase, some offers ask you to make a deposit or make a purchase but you are able to skip an offer and choose a different one.
Make sure you complete the offers properly or they may reject it and you won't get paid for that particular offer.
Share your referral link on Facebook, Twitter and anywhere else you can think of to earn referral bonuses from your pals. You will get a percentage of every offer they complete so encourage them to complete all 20 cogs! As you can see, I've managed to build up a good referral balance.