The Corona Mill is a cheap alternative to the more expensive roller mills used to crush grains for brewing. Roller mills start at $100 and quickly go up in price. A Corona Mill can be had for as little a $20. With three modifications---two minor, one a little more intense---it can be as effective or even more effective at crushing grains for home brewing. The lower cost will let you save money on other things like good brewing kettles, jet burners, and pumps.