Something a little different. An Overhead Projector calculator. By Stokes Publishing Company but built to emulate the FX-300W and a couple of similar models. : r/calculators
Smartphone Projector Calculator | Your DIY Smartphone Projector Guide
Easy Projector Throw and Screen Size Calculator - YouTube
FIRST LOOK: Audio Advice 3D Projector Throw Distance Calculator - YouTube
Easy Projector Throw and Screen Size Calculator - YouTube
Canon Projector Throw Distance Calculator / Download | Canon global