WordCounter.net - Count words, sentences, paragraphs etc.
Word Counter - A simple, beautiful word and character counter
Word Count Tools - The must-have free word counter that provides an extensive report about the word count, character count, keyword density, readability & many other useful stats.
Heytools - JavaScript tools, AJAX tools and some fully server side tools.
TextPipe - Search and Replace, Find and Replace, Web Sites, Database Extracts, XML, CSV, Tab, mainframe COBOL data and more
Wordcounter for Google Docs - A real-time word count and milestone markers in Google Docs.