Writers' block would be more aptly named "writers' boredom". 99.9% of the time, writers' block simply occurs because the author is bored. I have a three-step process for dealing with this.
1. Step away from the computer. 2. Lie down with my eyes closed and brainstorm. When did I get bored? What can I do to make it not boring? Will it be as simple as dropping a bomb right now, or will I have to delete the last 20 pages and start again? 3. Get my bottom back in the chair and don't stand up again until I've made some headway.
Writers' block -- I mean boredom -- is deadly. Because if the author gets bored, so does the reader. And if the reader gets bored ... the author is toast.