I have seen several posts where people use a ball mill to crush up the flat packs and such. To buy one of these setups is kind of expencive. I have seen other home made ball mills on youtube and other sites. These look like they preforme well and aren't that expencive. But, I had another idea. There seems to be a whole lot of people wanting to get rid of old laundry dryers. Most of these are less than 20 bucks or free. I was thinking that if the heating element and blower were disconnected and you sealed up the drum where and the lint trap you could use an old dryer. Im sure it wouldn't last too long from the abuse of ball bearing bouncing around in there. But, it is super cheap and can be taken by an appliance scrapper once it is destroyed. Has anyone used this method and how did it work for you?