Century Dictionary Online - American dictionary with fulltext search page images representing the definitions, atlas, and cyclopedia from the original text.
Vocabulary of Alliteration - a dictionary of alliterative words, for use in writing poems, songs, and studying phonetic and phonemic syllable divisions in English.
Voycabulary - lets you look up words in online dictionaries and thesauri by entering a URL or paragraph and clicking on the words. Supports many languages and translations.