There are no standards for HTML email, and this bugs me every couple of months when I have to design a new HTML email template because there's so much testing involved across different browsers, web mail systems and installed clients.
It would be so much better if everyone worked to an agreed set of standards, which is what the Email Standards Project is trying to do. http://www.email-standards.org
One day I'm hoping everyone will support CSS embedded in document head, but until then it's fiddly in-line styles on just about every markup tag. Still there are many that don't think we should be even trying to style HTML emails, (Jeffrey Zeldman who I hold in high regard being one) and say it's just a message format.
Balsamiq.com offer a desktop tool to speed up the process of designing user interfaces.
Very geeky example of what can be done with newish HTML canvas tag in modern browsers – i.e. not Internet Explorer (yet).
Reading about the web offline might seem counter intuative, but sometimes the slower more reflective pace of “books” is what's needed to digest other peoples ideas, and to spark off you own..
I've been doing some of these for work, back to tables and non-CSS design.. it's a slow process and there's still no standards but this list helps with the best practices…
Logo Tournament lets you harness the collective creativity of a number of designers when you need a new logo designed.
You put up a prize amount, provide some information about your organisation and leave it to designers to come back with their ideas. The designer providing the best logo get the prize fund and you get to use their design.
Sixteen sites that offer some inspiration (i.e. ideas to borrow) to web deisgners
Very simple website, emails when your website goes down or when it comes back up again.
Released under Creative Commons, Crystal Clear is a set of icons free for any designer or developer to use.