I'd give it a 9 - right up there with nose picking. Do that at home if you must be not in public. I hate feet anyway though - even sandals on men gross me out.

I'd give nose picking a 9.7. ;)

ten. truly disgusting.

i also find wiping one's face with those gross clothes in first glass pretty awful but i would only rank it a 7.

It barely bothers me at all. Granted, if I ended up with bits of nail flying about the cabin and landing in my drink, I'd probably get slightly riled. But really, it's just another (exposed!) part of the body, there are infinitely better things in the world to be disgusted by.

I would also give spitting on the floor a solid 10. Not common in certain countries but if you go to places like Mainland China, you'll know what I'm talking about.

Picking noses is gross...10 at least!

I also hate people who breathe their fumes all over you on flights, smelling of stale alcohol and yet try and chat you up! hahahahahahaha.........

Dirty fingernails.....smelly clothes...................don't get me started............:):)

Taking off one's socks in public would also earn a solid 9!

I saw a woman in rural China squat down by the side of a building and take a dump. After seeing that, on top of all the mucus hacking performed by everyone in that country, nail clipping is about a 1 or 2.

All public toilets in China are squat-down types. But yes taking a dump in a toiletless object is a common sight in the rural areas of the mainland. I've also seen them in the rural areas of Indonesia.

how about "and then SMELLING the socks" as I observed one businessman doing in the Admirals Club at LHR

nai clipping would only rate a 4 or 5 for me - though that would go up to 10 if the clippings actually fell on me