I have found br3ttb's Tapered Pocket Coin-Op bottle opener (http://www.thingiverse.com/thing:12348) to be a nice 3D printed souvenir to hand out. I started customizing the handouts for various occasions with different text on the body and now I have made that an easy thing for anyone to do via Customizer! I also thinned out the rear of the keychain hole so it is easier to attach.
Print at 90%+ fill or risk failure during opening. Only US 1 Cent slot tested on a Replicator 2 with Sailfish, print at your own risk!
Read the instructions for more information. Enjoy!
In Customizer you can can customize the text, adjust the coin slot and build a plate of bottle openers. The model is a complicated and can take some time to render the preview so be patient!
I found some coins lying around the are near the size of a US Cent and added my measurements of them to the script. I have not tested the fit with these foreign coins so don't print a full 20-opener plate before testing a single opener works with you coin of choice.
I also added a "manual" coin mode that allows you to tweak the coin slot size. For convenience, here are the values built into the script:
US 1 Cent: Radius=9.5 Thickness=1.75 Overhang=3
CA 1 Cent: Radius=9.5 Thickness=1.97 Overhang=3
EU 5 Cent: Radius=9.4 Thickness=2.11 Overhang=3
UK 1 Penny: Radius=10.2 Thickness=2.07 Overhang=3
If you find our coin of choice doesn't fit, adjust the numbers above slightly. The coin should squeeze into the slot after the print is finished. I use pliers to full seat the coin in the slot.
If you find a slight tweak of the numbers make a specific coin fit let me know and I'll change the values in the script. Also if you have tested measurements for another coin that should be included let me know an I will add it.