Im tired of stuff piling up. We always see fun things on vacation and buy them as souvenirs, but a few weeks later, it's just in the way. After a lot of years, you have boxes of old souvenirs.
So I take photos. However, I hardly ever look at them. Memories of fun with friends and family, and the warm feelings they bring, are still the best souvenirs.
I like shot glasses because they are small, but for my wife it's coffee cups. We have about 50. I think my kids break them on purpose to make room in the cabinets. Can't blame them.
I travel full time, so buying 'stuff' is just not something that's at all possible.
Usually though, I'll buy a sticker and put it on my laptop or my water bottle. It's lightweight and carries a memory without taking up any space.
I've been taking pictures of elevator buttons for a few years now. My job gets me into a lot of elevators in a lot of different places. Idk why, it's just like a quick, easy, and weightless souvenir.
Photographs. My photographs, to be specific. Maybe, on occasion, if it really resonates me, something of local cultural significance. (These can vary wildly from simple charms to complicated works of folk art.)