Low profile MTB Helmet – such a thing?

Is there one make/model of helmet that is a lower profile than others, y’know close to the head, not very thick – not compromising safety though, most of them look like a great big cherry stuck on top of my head, is there such a thing or do they all have to be a minimum thickness, surely there’s some materials that may offer the same protection for less material, if that makes sense?

The Xen has the pisspot skate-helmet styling for trail riding. Other than that, I know there is a beanie with the D3o ballistic gel.

That beanie is interesting . . . but £40 for a woolly hat when a pi$$pot can be had for a little over £20 😕