I've noticed that a lot of coaster nerds have large collections of t-shirts they've bought at the parks, so I assume a lot of the members of this site have plenty of them too. Feel free to post pictures of any coaster or park-related t-shirts (or any park apparel) you own here.
I bought this "Adrenaline Junkie" t-shirt at Valleyfair about two years ago.
Got this t-shirt of the signature coasters at Cedar Point when I was there back in June.
I have more park/coaster shirts, but this is all I'm sharing for now.