In my previous site design I had a “Share this on Twitter” link at the bottom of every article. But as I watched and measured the use of that button I found that people were organically sharing my articles on Twitter at a ratio of 5-to-1 those who were clicking the “Tweet this” link.
If you liked this, you'll love my book. It's called Designed for Use: Create Usable Interfaces for Applications and the Web. In it, I cover the whole design process, from user research and sketching to usability tests and A/B testing. But I don't just explain techniques, I also talk about concepts like discoverability, when and how to use animations, what we can learn from video games, and much more.
You can find out more about it (and order it directly, printed or as a DRM-free ebook) on the Pragmatic Programmers website. A Chinese translation is available from Amazon.cn.