In Japan, the 5-yen coin has a hole in the center to thwart counterfeiters. It's also said to bring good luck and love. People often string them together for blessings.
The 1-cent coin in Canada features a maple leaf design and is known as the 'penny'. It was discontinued in 2013, but some still use it for nostalgic reasons.
The 1974 aluminum 1-yen coin in Japan was considered unlucky due to its light weight and association with the oil crisis. It was eventually replaced by a heavier coin.
The 2-euro coin from Greece in 2002 featured a rare mistake with the letter 'E' resembling the euro symbol. Collectors value this error coin for its uniqueness.
The 10-cent coin from Australia in 1966 was mistakenly minted with the word 'DECIM' instead of 'DECIMAL'. These rare coins are highly sought after by collectors.
The 20-pence coin from the UK in 2008 had a design error where the date was missing. These coins are considered valuable and are sought after by numismatists.