Fr. Tucker..
links to a post on liturgical screw-ups.
I've noted a few on my blog before, such as the reader who announced "A reading from the letter of St. Paul to the Philippines", and the one who said that when Abraham was to sacrifice Isaac, he went to "the land of Moria". However, the best example I know of happened when I was not there...but boy did I ever hear about it !

A group of students on retreat were praying . The words were on copied sheets, not in books. The reading was from Isaiah, and it included this verse.

Sharing your bread with the hungry, sheltering the oppressed and the homeless; Clothing the naked when you see them, and not turning your back on your own....

Isaiah 58:7

Suddenly, the whole group burst out laughing. A "w" had been left out, so they were being urged to "clothe the naked hen" !