I bet everyone knows that Viking Direct offers free DVD player for purchases over £35.
This is what I did, I wanted that free DVD player so added 50p pens into the basket and the DVD player of course. But the delivery charges is about £3, so I cancelled the pens and checkout with the DVD player. Seem like I can checkout the DVD player without any orders!
Probably this is just an error on their website, but worth a try I think.