The world of numismatics, or coin collecting, indeed holds some rare and valuable coins that can make collectors quite wealthy. If you happen to possess certain rare or historically significant coins, they could indeed be valuable. Here are a few examples:

1794 Flowing Hair Silver Dollar:
The 1794 Flowing Hair Silver Dollar is one of the first silver dollars minted by the United States. In good condition, this coin can fetch millions of dollars at auction.

1933 Double Eagle:
The 1933 Double Eagle is a $20 gold coin produced by the U.S. Mint. Only a few were officially released, making it extremely rare. One of these sold at auction for over $7 million in recent years.

Brasher Doubloon:
Minted in 1787 by goldsmith Ephraim Brasher, the Brasher Doubloon is considered one of the rarest and most valuable coins. Only a handful exist, and they can fetch millions at auction.

1913 Liberty Head Nickel:
With only five known to exist, the 1913 Liberty Head Nickel is a highly sought-after coin. One of these coins sold for over $3 million in recent years.

1804 Draped Bust Silver Dollar:
The 1804 Draped Bust Silver Dollar is known as the "King of American Coins." Despite the date, most were minted in the 1830s. Owning one of these can make a collector exceptionally wealthy.

2007 Queen Elizabeth II $1 Million Coin:
Issued by the Royal Canadian Mint, the 2007 Queen Elizabeth II $1 Million Coin is made of pure gold and weighs about 100 kilograms. As a collector's item, it holds significant value beyond its face value.

1907 Saint-Gaudens Double Eagle Ultra High Relief:
The 1907 Saint-Gaudens Double Eagle Ultra High Relief is a masterpiece in American coinage. While a few were produced as high-relief patterns, the ultra-high-relief version is extremely rare and valuable.

2000-W Library of Congress Bimetallic Ten Dollar:
Issued as a commemorative coin, the 2000-W Library of Congress Bimetallic Ten Dollar coin is made of platinum and gold. Its limited mintage and precious metal composition contribute to its value.

1974-D Aluminum Lincoln Cent:
Although not intended for circulation, a few 1974-D Aluminum Lincoln Cents were struck and subsequently confiscated by the U.S. Mint. Possessing one of these could be highly valuable.

1955 Double Die Lincoln Cent:
The 1955 Double Die Lincoln Cent is a rare error coin with a distinct doubling of the date and inscriptions. In good condition, it can be worth a significant amount to collectors.

It's important to note that the condition, rarity, and historical significance of these coins greatly influence their value. Additionally, the value of coins can fluctuate based on market demand and other factors. If you believe you have a valuable coin, consulting with a professional numismatist or coin appraiser can help determine its true worth.