WC3 HTML Test - HTML, XHTML, SMIL, MathML, etc
http://jigsaw.w3.org/css-validator/

http://validator.w3.org/check?verbose=1&uri=http://minisites.dev12.visionteam.dk/

MobileOK content:

http://validator.w3.org/mobile/

http://validator.w3.org/mobile/check?task=20100205161109564&view=cat&docAddr=http://minisites.dev12.visionteam.dk

Links

http://validator.w3.org/checklink

http://validator.w3.org/checklink?uri=http://minisites.dev12.visionteam.dk&hide_type=all&depth=&check=Check

Validators / tools

http://www.w3.org/QA/Tools/