Looking through my collection, I came across a copy of Ducktales that I had absolutely ZERO CLUE where it came from. Im guessing someone gave it to me because it didnt work. I opened it up, and it was DISGUSTING inside.
Ive seriously never seen a PCB that messy before, something had obviously spilled on the cart years and years ago, seeping through at the contacts and the screw hole of the cart. It looked pitch black, as if the board has been dipped in oil. However, alcohol wipes did their magic, rubbing off whatever was stuck on there (it rubbed off dark brown, so coke maybe?), leaving the PCB shiny and clean.
And it works! Game rescued.