Memorabilia from Muhammad Ali, one of the greatest boxers of all time, has sold for millions of dollars. On July 24, one of Ali’s championship belts was sold for $6.18 million — making it the highest price fetched by a sports collectible sold at Heritage Auctions — according to CNN. And, it was not an easy feat to get one’s hands on the boxer’s belt from his 1974 “Rumble in the Jungle” heavyweight title fight.