Why do you make this your problem, if it is your other co-worker who is the most troubled by the Picker?
Buy him a bag of suckers. The kind with the soft loop for a handle. This way he has something for his hands and his mouth to fiddle with.
I once had a coworker who would chew on pens. Not just put the end in his mouth, he would have the thing half chewed to shreds in 30 seconds.
I bought him a bag of suckers, and every time I saw him pick up a pen I’d throw a sucker at him and say “chew on this instead!”
Didn’t work.
It already is my problem, for the reasons outlined above - how this plays out may have significant and long-lasting effect on the way the team works (or does not)
“For fuck’s sake man, just give it a rest will you. Nobody here wants to <experience in some way> you <indulging in minging habit >”.
Worked for me in a similar small team with someone who chewed gum all day like a particularly slack-jawed cow eating a turnip. Some people are just socially clueless (and, yes, this was in IT) and they just need to be told.
I’ve always taken the approach of pretending that the problem here is me. As in: “Oh hey, coworker dude, I realize this is sort of strange, but it really freaks me out when I see you eating your earwax. It would be a really huge favor to me if you could hold off on doing that until after work hours.”
This makes it less embarrassing - you’re not accusing them of being gross - and it makes them look like the good guy for accommodating you.
You mean like your grossed-out coworker who’s going to barf at any moment?
I’m thinking that the three of you should show up with really elegant linen napkins tucked into your necks, and demand that he share. Of course there’s always the chance that he’ll take you up on it.
Seriously, it sounds like the guy has OCD. He knows he’s doing it but he can’t stop. You might try complaining to a higher-up, but there’s probably nothing anyone can do about it . . . short of helping him get professional help.
Offer him a tissue next time you see him do it. Repeat from time to time until he stops. If he doesn’t, maybe have the others do the same. If he still doesn’t, at least he knows that other people are noticing it and it’s been talked about, which might make it a little easier to talk about it more directly later.
I thought what happened in IT stayed in IT. Apparently not.
Miss Manners says its all good as long as he doesnt smack more than once.
Is his name Patrick? I went to school with someone like that. He ate other stuff, too, pencils, paper, his sweater … we never loaned anything to Patrick that we wanted to get back.
IMO the best approach is for one person to take him aside in a non-confrontational manner and talk to him about it. I think reporting him to a boss or HR would be more embarrassing for him and provoke more harsh feelings.
Does he clip his nails at his desk and eat the clippings, too? Because that would really be the end-all!
But really, one solution you might bring up for him, if you have the quiet “just between us” conversation, is to cut the nails as short as possible, then super-glue the space left between the nail and nail bed. Can’t do any scooping if there’s no nail gap to scoop with. It doesn’t hurt, doesn’t do any harm, will peel off in a few days, and doesn’t interfere with typing or other tactile tasks. It will help break the habit. Possibly.
Someone needs to say something, and the near-vomiter is probably not the one.
He bites them, and the skin around them, and eats the bits he chews off.
Well then, sooner or later he’ll run out of fingers to pick with!
My teenage son had a terrible habit of chewing and smacking audibly when he ate. After trying other methods, I started saying, calmly and neutrally, every time he did it, “Please chew so I can’t hear you.” I’d say it in the middle of an ongoing conversation, whenever. He has reduced that behavior considerably.
You’ve established that he apparently does realize that he’s doing something that he recognizes makes other people uncomfortable.
What if, whenever you or your other two team members catch him at it, you say calmly, neutrally, “Please don’t do that.” The first time, he may ask, “Do what?” Respond with, “Picking and eating your ______.”
If every one of his team members says, “Please don’t do that,” whenever he does it, he may at least understand that he can only do it when he’s home alone.
Incidentally, the behavior has a name: dermatillomania.
I agree, if he knows it makes other people uncomfortable and does it anyway, it sounds like an OCD type thing (dermatillomania it is!). Doesn’t matter, though - OCD or not, you can’t do that in public. Can you bring it up with him and find out if he does indeed have dermthingy, and if he is in treatment for it? If so, I would try to stick it out and see if he gets better, but seriously, I would quit over something like that if he isn’t working on it. I don’t have many things that turn my stomach, but that’s one of them.
I vote for silently handing him a tissue each and every time he does this. You said he does it in face-to-face conversation…just always have a tissue ready, when he starts digging, hand him the tissue. Don’t say anything…just shove it at him. Each and every time.
God, I wish I had no shame.
Then watch him eat it.
Seriously, I would not normally advocate making other people uncomfortable but that is really fucking disgusting and I can’t imagine not saying something to him the next time he gnaws on a scab in front of me.
I used to pick at my fingers and bite them in front of people until a coworker and very good friend looked me dead in the eye and said “Do you realize how completely disgusting that is to watch?” I still do it, just not around people (as much).
ETA: I see runner pat has beaten me to the punch on the vomiting. But I did discover the word dermatillomania and wonder if that’s what I have because my fingers look kind of like they went through a meat grinder and it hurts but I can’t quit.
I personally would have commented on it the very first time I saw it, and would continue to give him shit about it as time went on. Not in a mean spirited way, mind, but friendly prodding.
OTOH, were I him, and I knew that those activities bugged you that much, I would redouble my efforts.
Juvenile, sure, but I have fun. 
Is there a team lead you can approach without going to a management level? Otherwise, I suspect that you are going to have to step up yourself.
It may be that your picky co-worker does have a problem that means that this behaviour is non-elective - if that is the case then avoiding creating a hostile workplace environment will be paramount.
A request to reorganise the desk space in a way that does not impede communication but breaks up the sight lines may help. Or requesting 2x36" monitors on every desk for Business Requirements 
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