I couldn't run my fridge in my mom's ( steeply sloped ) driveway during a recent trip, but wanted to pre-cool the fridge before we left, and found that stainless steel mixing bowls filled with ice, and then placed ( one in the freezer and one touching the cooling fins in the fridge ) so they were touching the metal fridge parts did an excellent job of transfering the heat, and pre-cooled the fridge to a nice low temp in just a couple of hours. I think the heat conducting properties of the metal bowls is the thing - the fridge was down from 75 to 45 in no time, and all the metal parts of the fridge were nice and cold before we lit it for the return trip. Hope someone finds this useful -