Technically an adult but not old enough to drink.
Au contraire (that's French), for we're speaking in terms of internet years, akin to dog years, of which there's a formula to calculate the real age of a dog.
After penning the above (seriously, even though it uses the same analogy), I hunted Google and found the following:
http://www.fatdux.com/blog/2009/09/22/calculating-the-length-of-an-internet-year/And that means X = 4.7 years.
So, it seems that Bitcoin can legally buy and drink NEFT Vodka most anywhere in the world, for it's clearly over 21.