Writing Outwardly
Wikipedia exemplifies this as its main and arguably only function is to help users find information about almost anything. The home page gives the user a choice of language before providing options, from news of the day to random pages that may be of interest. Whether looking for something specific or something new, wikipedia puts out its information for the user's benefit.
Not burying the lead
I found this site while I was doing research on my finals topic, and I thought it would be a good example for this. It makes its point immediately, before going into secondary information the user might be interested in after the primary has been answered.
Not saying too much
I recently found this site for practicing life figure drawing, and I think it works as a really good example for this. Unlike some sites I've found that offer so many options it feels confusing to find what you want, this one is really straight-forward, giving you some simple parameters to choose from and then when you are ready, gives you a selection to practice drawing. It is really simple and I appreciate how easy it is to use; wonderful functionality without wasting space on unnecessary words.
Making a strong call to action
When thinking about calls to action, I'm reminded of the marines ads I would often see. They all shared common themes, but a call to action, as in, to join the corps, was always strongly accompanied by themes of defense, commitment, and sharing a collective purpose. The site itself continues that call to action.