The Phono Horn is a free downloadable paper sound dock kit designed for paper model and DIY enthusiasts looking to passively amplify the audio coming from their smartphones in colorful fashion. You're not going to impress any audiophiles with the results, but the fun design should win over everyone else, while adding a few decibels in the process...
There are separate editions available for the iPhone 4S, one for Samsung Galaxy S2 and S4, and a new one for the Samsung Galaxy S3. You'll need 67lbs weight A4 cardstock paper in a selection of colors fit for your preference, glue, and a lazy afternoon to get building your own phonograph style dock+amplifier. This seems like an ideal project for a parent and child to work on together during a weekend or evening, with plenty of opportunities for customization.
Step-by-step instructions of Rob Ives Phono Horn kit available here.
(Images: Rob Ives)