Total Validator Tool
Why use separate validation tools to check your web pages when you only need one? The Total Validator Tool performs the most important validations on your web pages: True (X)HTML validation against published W3C/ISO DTDs; accessibility validation against the W3C and US Section 508 guidelines;... Spelling is often left unchecked and will make your site look and feel unprofessional and even unusable. ... Broken links are the bane of every webmaster, you may get your internal links correct, but external sites tend to change all the time, and there's nothing that makes your site look worse...
http://www.totalvalidator.com/downloads/TotalValidator_F200.exe - 2Mb - Download - Screenshot