WordPress CMS Web Application Framework (open source)
Joomla! CMS Web Application Framework (open source)
Drupal CMS Web Application Framework (open source)
Alertra.com (check the speed of your website)
Google Analytics (free website traffic statistics)
Google Adsense (“Ads by Google” on your site)
Alexa (leading third-party website traffic monitor)
Quant Cast (third-party website statistic monitor)
WidgetBox (find widgets for your website or blog)
SEO-Browser.com (see your website like Search Engines see it)
WebsiteGrader.com (evaluate your website’s marketing effectiveness)
W3C Markup Validation Service (check for clean website code)