Pitch:

I'm going to go on Dragons' Den and present my new invention: the Convex Bath.

It's like a normal bath, except convex. It's basically a fibreglass bathroom mound. It's better than the normal bath for several reasons:

1) It's incredibly uncomfortable to lie on. Your spine bends backwards - you're painfully prostrate. Extended use leads to paralysis.

2) It obviously can't hold any water. The tap is above you, and provides an inefficient trickle shower.

3) The plughole is right at the peak of the Convex Bath's hump. Which means your body is always covering it, leading to no drainage whatsoever; eventually causing flooding to your bathroom. With water pouring into your house, you're bound to face mould, structural instability, and eventual death.

4) The plughole is also really, really sharp, and cuts up your back.

5) When you're all soaped-up, you won't be able to maintain any traction, so you'll keep sliding off the jagged hole and onto the sodden bathroom floor. Bleeding and hypothermia are your only friends.

What do you think?

I reckon it would fit well in any trendy inner-city wankpad.