for our six month anniversary my girlfriend got me a custom cigarette case that i used until i switched from shorts to longs (and then started using to carry joints.)
similarly, my friend made custom lighters for everyone that helped him work on a photoshoot / project with some motifs from the shoot
i think paraphernalia is cool because it becomes a constant fixture in your day to day (yikes) and attaches a memory / individuality to something that you're doing constantly - i think in terms of a less destructive way foster this, stationary like pens or notebooks, phone or computer decals, etc. where it's just more personalized is the way to go, but that ultimately depends on the person and their habits :)