I like Crowdology in particular as it's different to most survey sites. They do have some of the usual boring surveys that all survey sites have, but they also have quickfire one minute surveys that are sort of like a pub quiz, like asking you to name as many of Adam Sandler's films as possible and things like that. You get paid for all surveys and although the one minute surveys only pay around 24p as they only take a minute to complete (sometimes less) it's well worth it and they're enjoyable as well. They pay better than most survey sites in relation to time spent and they also pay out immediately via Paypal when you request it. Plus, you can cash out as soon as you have £4 or more.