I've made a coaster which you can fold so it's easier to carry around when traveling or camping! It also serves as a bottle opener when it's folded up. So you can put it in your pocket and be ready to have a drink anytime anywhere!
I printed it in PETG but PLA should work just as good, though maybe the bottle opener won't hold up as well. Infill really doesn't matter (I'd recommend over 20%) and no supports are needed, everything prints in place, ready to use. The hinges might be a bit stiff at first but you just have to carefully loosen them up.
I haven't tested the bottle opener yet, I don't have any unopened bottles so if anyone does, please let me know how it did.
The author marked this model as their own original creation.