I've recently stumbled across slide joy which rents your lockscreek space in order to generate you karats which are redeemable for PayPal cash, on steam and some other online shopping sites. Not only that, but you earn more karats for downloading apps, taking surveys and playing games!
I've cashed out 2 euro to make sure it works and it does. You can also see other people's cashouts, leader boards etc.
Please use my referal code below which will enable you to obtain your own referal code for your friends and family etc.