WritersHQ is a UK based company that offers training and retreats for writers. On their blog, they publish blog posts "of between 500 – 800 words examining writing and the writing process from a new perspective." They also seek posts on monthly themes. They pay £40 for all posts. To learn more, read their submission guidelines.
The SFWA Blog is the official blog for the Science Fiction & Fantasy Writers of America. They want nonfiction articles of interest to sci-fi/fantasy writers. They pay 8 cents a word, up to 1,000 words. To learn more, read their submission guidelines.