Give as You Live* lets you raise money for your favourite charity, by shopping online. It works in the same way as TopCashBack and other cashback websites, except that the cashback goes to charity instead of you. Basically, they earn commission by you clicking through from their website and they pass a percentage of that cashback on to your charity.
You can choose any UK registered charity, so it is completely up to you who you raise money for and it is a great way to give money to charity for free.
Of course, if you choose to use Give as You Live instead of other cashback websites that pay you, it's not really free, because you are missing out on cashback. However, there are many websites on there, including John Lewis and Amazon, that are not on other websites. So, if you only use it for websites that are not on other cashback websites, you are basically giving money to charity for free.
That is exactly what I do! Before buying anything online, I check if the website I'm buying from is on TopCashBack. If it isn't, I check Give as You Live. I've made just over £35 for my charity, in about a year, which isn't a huge amount, but if everyone did the same thing, it would be loads. So go sign up!
*If you join through my referrer link, my chosen charity (CRY - Cardiac Risk in the Young, at time of writing) gets and extra £5.