I have some souvenirs/totems in the form of journals of conferences I went to or spoke at, and some cases of computer games I really liked. But mostly they also exist as digital copies and only collect dust in my home. But whenever I dust them off, they remind me of the time, which digital copies would not.
I explore the Rocky and Columbia mountains and icefields very often, so I have a nice array of very interesting pieces of geology and fossils in my house (including many precious gems from around the world, such as my 4' tall amethysts).
I also have a few small memorabilia from movie sets that have been set up in my area (for example, I have a small wooden stake with rope around it that was used as a TP stake in The Revenant (which I just went and saw this past weekend).
Other than that, I have a fair amount of artwork from all over (mostly street art that artist friends put on paper/canvas for me), and many pieces by my step-daughter (she's an artist in the Bay area).
Besides those (which are not in abundance), I don't have much stuff; I dislike clutter.
It is amazing how much stuff can collect on shelves, walls, on flat surfaces.... none of which have any real functional value. I have to admit however, my wife has amazing taste and a unique ability to present this stuff in a non-cluttered way. To her goes the blame, but mostly the credit. This old farm boy has no class, which is my style. But I do recognize it when I see it, and the lady has class and shows it, including the way she picks out and presents 'stuff'.
...the majority is always wrong, and always the last to know about it...
A solution is nothing more than a clearly stated problem...
For those familiar with Keirsey's temperament theory: Guardians (or, by extension, spouses of Guardians) are the most likely to have an extensive family photograph collection and to display photographs and trophies. As the theory goes, this is how they show they are participating in society.
Not that the other types don't have them. But, in general, they pale by comparison.