Instead of coin collecting piggy bank I decided to design and print a coin holder for Euro currency. Added four different versions, each version has a different calculated (!) money capacity. Starting at 25 EUR, there is a 50 EUR, 75 EUR and 100 EUR version. Check out: http://youtu.be/_vjwDb5efZo
Printable without support. Pictures and video show the 50 EUR version. 5 hr PLA print on Up Plus 2 (see video description for more info).
Update #1: Added a version without 1 ct, 2 ct, 5 ct. (Requested by ioanniskar). Doubled 10 ct, 20 ct, 50 ct slots.
Update #2: Added a 5 ct insert for the STLs published with the update #1 files. Thanks WeakNerve for the idea!