Bare Conductive - Electric Paint Pen is just like any other water-based paint, except that it conducts electricity! This means that you can paint wires or sensors directly onto almost any material around you, including paper, wood, plastic and glass.
39.99$ Watch here - https://alitems.com/g/1e8d114494b01f4c715516525dc3e8/?i=5&ulp=https%3A%2F%2Fwww.aliexpress.com%2Fitem%2FDigital-Conductivity-Meter-Conductivity-Tester-Water-quality-tester-Conductivity-pen-ATC-0-1999uS%2F32745176816.html - Digital Conductivity Meter Conductivity Tester Water quality tester Conductivity pen ATC 0-1999uS
Electroninks Incorporated is raising funds for Circuit Scribe: Draw Circuits Instantly on Kickstarter! Circuit Scribe is a rollerball pen that writes with conductive silver ink. It makes creating circuits as easy as doodling.
There are Arduino Shields open source hardware project. We modified the normal method with crafting idea to decrease the cost of prototype board and conductive pen. We made PAPERduino "stable" decreasing the cost more... https://thecustomizewindows.com/2015/12/build-own-arduino-board-paperduino-arduino-shields/