I defy anyone to look at this chart and not want to grab the nearest obliging man, tape measure in hand. It appeals to both my scientific side and my 'always on the lookout for great sex' side. And it looks like a pretty technical chart, right up until you read the key, the colours corresponding to ideal, very satisfying, satisfying, enjoyable and "not satisfying: too small in length and girth, or too big in length and girth, or any freaky combination of small and big". At this point, it descends into the kind of non-scientific conversation I generally have with mates after a night of cocktails.

Having examined it for the sake of science, I hold a certain amount of sympathy for the men. Having been told 'it's not the size, it's what you do with it' by kindly women across the world for years, we've left them with just an inch length-ways and half an inch girth as margin for error, if they want to fall into the 'perfect' category. And that doesn't even take into consideration other factors like body odour, saliva levels and questionable chat during the act...

For more penis-sized debate, check out there site here.