William Zinsser's On Writing Well, about writing non-fiction articles, has a lot of examples of people (including scientists) writing beautifully about complex topics, and talks about style, audience, your voice etc. It's a very inspiring book.
re blogging, I've found Jeff Atwood's articles on blogging on his Coding Horror blog to be wise and very helpful. Also Julia Evans' blog is a great example of someone sharing what they're learning in an inspiring, energetic and fun way.