This site collects unusual spellings of a particular kind, which have come to be called eggcorns. Typical examples include free reign (instead of free rein) or hone in on (instead of home in on), and many more or less common reshapings of words and expressions: a word or part of a word is semantically reanalyzed, and the spelling reflects the new interpretation.
The About page offers more information on the history of the term and of this collection.
The Eggcorn Database went public on February 15, 2005. New entries and features are being added regularly.