Have you too seen the nice "mail me" icons that sprout on blogs and web sites everywhere and stopped for a moment, wondering what makes them? I did some time ago, but didn't stop enough to actually search for a source, and cooked my own instead. (Hence the somewhat different size, adjusted to fit snugly in my blog sidebar.)
By a pleasant coincidence, I today stumbled on it (or one of them, anyway) in a post by Yukuan Jiang (in Chinese, so I assume you too might prefer to have Google translate it to English, or something close to it).
I whole-heartedly recommend giving visitors options for ways of contacting you; it gives a much better impression than anonymous blogs where it is difficult to get in touch with the author. Everybody wins, and images like these don't get crawled by spam bots either. Leave out the additional HTML
mailto:
link around the image if you are really paranoid about getting spam that way.