I have owned three AIM t-shirts; two of them were given to me as a student (one in each year). I never wore either of them after I left Lubbock, and I gave them both away long before I graduated from aim.
I got the third one my first weekend as an aim (can't be bothered capitalising every time) assistant. We were talking about the aim students' first day, Jason mentioned that we would all need to wear our aim t-shirts. Which prompted this conversation:
I: I don't have an aim t-shirt.
Aim Assistants (AAs): General gasp of shock.
Jason: What happened to your t-shirt?
I: I gave it away. Both of them, actually.
AAs: Repeat gasp of shock.
Benjy or Scott (don't remember which one, but it was certainly one of them): You gave it away?
B or S: Why?
I: My whole team did. We all gave them to people who were important to us.
AAs: Giving me a blank stare.
I: Look, I can tie my aim certificate around my neck if you want, because that's the only thing I own that says "Aim."
Jason (probably feels the conversation is straying from the purpose at hand): Okay, I'll get you another t-shirt Saturday morning.
And, the conversation only got better on Saturday:
Jason: Which size do you need?
Jason: Are you sure?
I: Yeaaaah. (Adding a couple of syllables to the word, in a way that I hope indicates "Let's not have a conversation about what size I am, okay?")
Jason (gets it): Okay.
I still have the debated t-shirt; the day after my second aim class left for the field, it became a workout shirt. And as a result, the t-shirt has been a feature at two (at least) West Texas Running Club races. And it still fits just as well as it did eight years ago.