Inctor tester with PCD8544 (Nokia5110) and a push button. Op-amp Comparator schematic is found here. Any Op-amp will work try and find one like the LM358n with better noise reduction and bandwidth for better range and accuracy.
Much thanks to http://reibot.org/2011/07/19/measuring-inductance/ for original source and schematics and addafruit for the LCD librarys