One of my co-workers bought her boyfriend a Che Guevara t-shirt and when I saw him wearing it I commented, "Oh. Che Guevara." It's the famous Guerrillero Heroico photograph, the one plastered on shirts in Hot Topics across America.

Co-worker: Huh?
Me: Your boyfriend's shirt. It's Che Guevara.
Co-worker: Isn't it a cool shirt? I got it for him.
Me: Really? Why'd you pick it?
Co-worker: I dunno, it looked cool. Why, is he famous?
Me: ...
...
...
...
a little bit. Political figure. Revolutionary guy down in South America and Cuba. Never heard of him?
Co-worker: Nope!

*sigh*
I'm all about cool-looking shirts, but know what you're wearing! Know what you're representing!