There are times when you’d like to have a certain type of post appear in a widget for use in your sidebar or (in some themes) your header or footer. The Random One Cat Widget allows you to do this. It will display any post, long or short, even ones containing pictures and custom fields, although it is best suited to small text posts.
On this site I use it to display a category of posts I called tips in the header. These are normally just one liners that I sometimes add to the site, but it will work equally well for any group of reasonably small posts.
You can download this Widget from the WordPress Plugin Directory.
There is the option to include the title of the post, the title of the widget, both or (like on this site) neither. The later offers a cleaner approach, but you choice is there for you should you prefer a header or two.
If you want you can add a bunch of widgets, each showing a random post from a different category.
There is also the choice to show any custom fields that you might have defined for the post. Just check the box.
You can now display up to five posts at a time.