A two-part snap-together case for the Raspberry Pi 2 (probably works also for the model B+). The two part design is intended to be printed with minimal support structures and to be tolerant to warping when printing with ABS. To make the case fit even if the front and back sides are slightly warped the back part has two slots for the edges of the Raspi's board that allow the board to fit in even if the case edges are warped. If you don't need that you can modify the corresponding Tinkercad file.

Front: https://tinkercad.com/things/jsU2tWXlk45
Back: https://tinkercad.com/things/faPvYSBrbJI

Disclaimer: use this case at your own risk.