"drink"

a word which, as a verb, can be applied to its noun form

"drink drink" is a valid sentence, with "you" as the implicit subject in the English 'subject->verb->object' structure

can you think of any words like this?

I can think of a couple others, like poop and fish ((you) poop poop and (you) fish fish), but not much else

shit shit
fart fart

I dont drink as I am simply to young. Turning the big two one this year!

Still won't drink though :/

Buffalo buffalo, etc.

Actually it isn't a valid sentence, there needs to be a determiner between the two of them, typically it would be an Article such as "a" or "the". The determiner cannot be implied like the subject can. Not to mention the verbs themselves already imply the involvement of the general object that you are restating, making it redundant. "Drink." is a valid sentence, but "Drink drink" is not. However "Drink drinks" IS but is poor form because a determiner should be included in that one too because of redundancy/ambiguity issues. What are you going to be drinking that isn't already a drink? Piss? Then it would be "Drink piss" which actually is a valid sentence whereas "drink drink" never will be.

Toast toast.

Roast roast.

Cream cream.

Mush mush.

Juice juice.

Stuff stuff.