I love prepaid cards. I love them because if you're crafty, you can always find a bargain that's significantly cheaper than simply paying face value. For today only, CDKeys have lowered the price on £50 of Steam credit down to £43.69, but by snaffling up a 5% off voucher code from Facebook, you can lower that even further down to £41.49.
NB. All CDKeys products "are delivered digitally via email, which includes the product code and the instructions."
Be sure to bookmark our games deals stream for further savings!