AlchemyAPI is a text mining platform that provides semantic tagging to over 24,000 developers in six continents, processing over 3 billion API calls per month (over 1,000 every second). AlchemyAPI is a product of Orchestr8, founded in 2005, providing the most comprehensive set of natural language processing capabilities of any text mining platform, including: named entity extraction, sentiment analysis, concept tagging, author extraction, relations extraction, web page cleaning, language detection, keyword extraction, quotations extraction, intent mining, and topic categorization.

http://www.alchemyapi.com