Are you developing with standards? This is a great place to check things out and stay current.
16 tips for figuring out why your HTML email doesn't look or work right. (from Litmus)
DOs and DON'Ts for creating HTML emails from Litmus, a stellar email testing service.
Oh man, I needed to do this today, and this example was so concise and perfect it made me overjoyed!
Use this when you have a bunch of domains forwarding to your main domain and you want to 301 redirect all of them to the www version of your main domain. 301 redirects (permanent redirects) are the good ones in terms of SEO.
Basically what it's saying is: For all domains that are NOT your main domain, redirect to your main domain. (e.g. redirect someotherdomain.com or www.yetanotherdomain.com to www.maindomain.com).
Add a text caption to your images.
Pixels aren't what they used to be. Scott Kellum explores new pixel definitions, different implementations on various mobile devices, and how to handle the resulting issues. From A List Apart.
Reference on using, cautiously using or avoiding various HTML5 and CSS 3 features, with fallbacks and requirements.