W3Schools has been a dependable companion to me for much of my web development career. Just yesterday, I learnt that the rel attribute of the anchor tag is not really supported by any major browsers and it can take over a dozen possible values. rel="nofollow" is used by search engines to let search spiders know they should not follow a link which contains that attribute.
W3Schools is currently ranked 341 on Alexa & enjoys over 103+ million monthly page views (March 2010).
Also see:
Free .NET 4 & VS 2010 Learning Resources
HOW TO block IFRAME based ads
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