collecting video games is not only my hobby, but a passion of mine. like most video game collectors, i use the ammonia in Windex window cleaner for cleaning the outside of the video games. windex isn't enough to clean the video electrical contacts. it does an okay job. it is certainly better than the dry CLEANING METHODS. when i was lazy i would prefer the safer dry cleaning or windex process. i found out quickly that i was cleaning my carts allot more than normal. the grit and corrosion would have to be scraped off the game's contacts. i find it more effective to open up the video game cartridge with this screwdriver bit piece. once opened i use a general wal-mart school eraser. to knock off corrosion i might use the metal contact of the nintendo bit, a paperclip, or an old key. metal to metal contact works great, but clr works even better to remove video game contact corrosion. applying it with a q-tip by simply rubbing it over the games' contacts is quick and easy to get off a lot of the corrosion, grime, and grit. it all has to start with opening the game. that is why i find this tool very valuable.