The silver Proof 5000 Kwacha coin issued by Zambia to commemorate the 2000 Sydney Olympics is one of the strangest shaped coins ever issued. The unusual coin was made in the shape of the conjoined maps of Australia and Zambia. Though Australia is approximately ten times the size of Zambia, the two are shown to be roughly the same area on the coin, and while northern Zambia is attached to Northern Australia, the countries are halfway around the world from each other! The large size coin is approximately 49mm x 42mm and contains approximately one troy ounce of silver.
Somali Republic’s 2004 commemorative dollar coin is shaped like a guitar to mark the 50th anniversary of rock and roll music and the Stratocaster guitar. The non-denominated side, left, is enameled. The multi-colored Guitar coins have proved unbelievably popular with coin collectors, guitar enthusiasts, Rock ‘n Roll fans and the general public. They are designed after famous electric guitars, including the classic red and white Fender Stratocaster, an American Flag Stars and Stripes Gibson Flying V, a black Gibson Flying V, a pink star Guitar used by various rock stars including Gary Glitter and Abba, a blue Gibson X-Plorer and a yellow Klein. The coins are 1 Dollar legal tender coins and they are approximately 45mm (1.75 inches) long.
Many other countries have issued diamond-shaped coins. The Bahamas’ 15-cent coins are diamond-shaped. First issued in 1966, the coins feature Queen Elizabeth II’s portrait on the obverse and a hibiscus on the reverse. Bhutan, India, Myanmar, the Netherlands, Oman and Pakistan are among other countries that have released circulating diamond-shaped coins.
The most oddly shaped coin has to be the .999 fine silver 2002 $10 issue from the Republic of Nauru, an island republic located in the western Pacific Ocean. The Proof coin celebrates the introduction of the euro with a coin shaped in the outline of the nations that comprise the European Economic Union.
Source: http://www.fleur-de-coin.com/articles/unusualcoins.asp