This interesting kit uses a mix of Tindie + Shapeways to sell a product that has a 3D printed case. From Tindie:
PressurePen is a pressure sensitive stylus for iPad and Android tablets.
Unlike a typical stylus, it communicates how hard the user is pressing on the screen with the tablet via a standard audio jack. With software support, a light press can render as a fine line, while a stronger press will become a wide stroke. PressurePen is an open source hardware project funded, in part, by Kickstarter backers.
The PressurePen pressure sensitive stylus connects to any iOS (including iPad, iPhone) or Android (including Google Nexus and Kindle Fire) device via a standard audio cable (included). It is powered by one AAA battery (not included).
This package contains the kit of parts necessary to build one PressurePen pressure sensitive stylus, one MicroStylus tip, and a cable to connect to your tablet of choice. It does not contain the plastic shell. One may be ordered separately from Shapeways.com or printed on a 3D printer. 3D files are available at Thingiverse
Make a robot friend with Adafruit’s CRICKIT – A Creative Robotics & Interactive Construction Kit. It’s an add-on to our popular Circuit Playground Express, FEATHER and other platforms to make and program robots with CircuitPython, MakeCode, and Arduino. Start controlling motors, servos, solenoids. You also get signal pins, capacitive touch sensors, a NeoPixel driver and amplified speaker output. It complements & extends your boards so you can still use all the goodies on the microcontroller, now you have a robotics playground as well.