Wolfram|Alpha is a great resource for writers. It has an enormous words and linguistics database that writers can use for such things as word definitions, origins, synonyms, hyphenation, and Soundex lookups.
Type “word contest”, and Wolfram|Alpha will retrieve the word data for the English word “contest”. The results tell you many definitions of the word, that its first known recorded use was in 1603, that it rhymes with “conquest”, and a wealth of other data on just that word.
Wolfram|Alpha also features tools that can calculate and find anagrams, word patterns, and transliterations. You can also search for words with specific letter strings. For example, enter “words ending in ation” and Wolfram|Alpha will show you all 1148 words in its dictionary that fit this criteria.