The Widow's Mite is a bronze coin, dating from about 100 B.C. to the lifetime of Jesus (at least - I don't know the full period of circulation). It gets it's name from a story in the bible, told in Mark 12:41

And Jesus sat over against the treasury, and beheld how the people cast money into the treasury; and many that were rich cast in much. And there came a certain poor widow, and she threw in two mites, which make a farthing. And he called unto him, his disciples, and said unto them, Verily I say unto you, This poor widow hath cast more in, than all they which have cast into the treasury; For all they did cast in of their abundance, but she of her want did cast in all that she had, even all her living.
and in Luke 21:1
And he looked up, and saw the rich men casting their gifts into the treasury. And he saw also a certain poor widow casting in thither two mites. And he said, Of a truth I say unto you, that this poor widow hath cast in more than they all: For all these have of their abundance cast in unto the offerings of God: but she of her penury hath cast in all the living that she had.

These coins were made by first producing a long, thin strip of metal between two dies. The end of the strip was placed between two striking dies, and hit with a hammer. Then the strip was pulled quickly, about the length of one coin, hit again, and the process is repeated until the end of the strip is reached. After all the impressions had been made onto the metal, the coins were individually cut out. The two striking dies were not fixed in place very well, so many of the coins have the pattern on one or both sides off-center.

The coin is about 1.2cm in diameter (about half an inch), on one side is an eight-pointed star and on the other is an anchor, sometimes with Greek letters written around it.