if you haven't come across it, it is a bottle of bubble bath with a section on top on which you push a button and a small plastic tardis lights up and spins around on the top, and then splits in two to reveal a small plastic figure of david tennant. a lovely item and much more releastic than the flight control tardis!
available at ASDA stores, £3.98. picked mine up today.
if you're asda doesn't have one or there isn't an asda near you, then here's a chance to bid on Ebay (has 2 days left):