When I was younger, my mother would always bring home Hard Rock t-shirts for me from her various trips. She has never had the opportunity to travel outside of North America, however so I have many shirts from the various US/Canada locations courtesy of her.
Since I've started traveling for work, I've had a chance to return the gifts to her with Hard Rock shirts from London, Paris, Berlin, Munich, Rome, Moscow, Cairo, Sydney, Beijing, Hong Kong, Singapore and Bangkok.
I visit them in every city I go to specifically to buy my mom a shirt and most of the time end up eating at them as well.
My personal favorite: Moscow.