Setting featured image for post/page could be very time consuming, especially when your media library holds hundreds of pictures. Very often we select the same thumbnail for posts in particular category. Wouldn't be much easier to have a thumbnail being set automatically when we choose a category while creating or updating posts/pages? I could not find in wordpress.org repository any plugins doing exactly what I wanted and decided to write my own. It started as a plugin just for myself. Exactly 12 lines of code. Then I decided to share it with others. And here it is - FPW Category Thumbnails. Click on a link above this post to see the plugin in WordPress repository.