Circuit Eraser enables us to erase/rewrite conductive ink traces on paper, again and again, resulting in the iterative design of hand-drawn/printed conductive ink circuit using the off-the-shelf and safe material. This project aims at solving the problem of novices, tinkers, and artists not having the tools for trial-and-error in their conductive ink circuit. This technique was commercialized by AgIC Inc. (Elephantech Inc.) and is now affordable for everyone.