A bicycle mount for the iPhone 5. To be used without a case. Mounts on most sizes of round bars both horizontal and vertical using the OpenSCAD file. A 4/4s version could be made with very slight modifications.
Edit: I added an OpenSCAD file for generating a clamp for a wide array of bar sizes as well as a horizontal option. (My first OpenSCAD file. Looks like it works well enough.)
Visit http://blog.rwillbrown.com/?p=183 for design insight and more information!
The clamp parts should print without issue as long as your printer can handle a mild overhang for the screw holes. You can attach them with 1/4" bolts or zip ties.
Edit: I added an OpenSCAD file that will generate a custom bar clamp that will fit the phone mount and still accept 1/4" hardware. There is also a horizontal option for mounting on the handlebars. The dovetail mount is offset on the horizontal version to eliminate an awful overhang. I'd hate to print this with support material, as the dovetail grooves need to be precise to align well. Let me know if you run into any issues!
For the mount itself, I uploaded the exploded version I use for printing on my Printrbot Jr. No overhangs. No problems. Just superglue the retaining pieces on the frame.
Sizing was an issue on my printer. It tends to make things a few millimeters too big. Your mileage may vary. I will upload the .skp in case you need to make changes.
Derivatives are welcome for noncommercial, but remember to attribute this page and myself.