Anything I already could do when I was 16 xD Only you've got to be 18 to drive a car here. Oh and vote.
But other than that most things were legal already, like going out to clubs (depends on what club, some are 16+, some 18+), drinking alcohol (till a limited percentage), drive a scooter and much more. So turning 18 isn't too special for us here except for being able to drive and vote.

Library card is consider plastic too. XD Plus I have like 15 plastic cards with me already and I'm not 18.

I'm more anxious to be twenty-one. I don't want to drink, but I want to work in a bar to make some extra cash.

Lets see... I can drive till whenever I want, but my insurance is super duper high. I can buy cigarettes legally, but I quit those. I can go to 18+ clubs, but I don't go clubbing. Well, I can do stuff at Gamestop since you have to at least be 18 to trade in things and get money, but I don't buy video games. OH! And since I'm a guy, if there is a draft to go into the military, my ass is on its merry way. Luckily for me, I have mental/physical problems, so no way am I going! c:

Annie: Here in Florida, you have to be at least 18 to serve alcohol, but have to be 21 to drink alcohol.

When I man plastic cards I mean debit/credit cards of your own. You have to be 18 and over to get one from your bank