You wouldn't have had Cliff Richard down as a man desperate to embrace the new - especially with his battle to try and preserve copyright on recordings he made back when he had motile sperm. But he's dipping his toe in the water by offering his next mainly-back-catalogue collection at a price which will become smaller the more people who sign up for it.
Of course, this is almost the same mode of pricing used by PriceDrop TV, and we imagine that many Cliff Richard fans will crossover with the television shopping crowd, so it makes some sort of sense.
Once again, it's EMI who are experimenting:
Unfortunately, there is a basement price set beyond which the cost will not fall, presumably to discourage people from signing up for several thousand copies to push the price down to a penny.