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.
I used this to display a random senryu on each page, but it will work equally well for any group of reasonably small posts.
There is the option to include the title of the post, the title of the widget, both titles, or neither.
If you want you can add a bunch of widgets, each showing up to five random posts from a different category.

Random One Cat Widget

This Widget shows up to five random posts from a given category

Farsad Fakhim

This is a simple plugin to add a widget to your website that loads random post(s) for you. 🙂
<h3>For Next Release</h3>
You can contact me by my Email (fakhimfrasad26@gmail.com) to ask for features but we are going to develop these for the next release : 
Image custom size

Random Post Loader

This is a simple plugin to add a widget to your website that loads random post(s) for you. :)

Random One Cat Widget vs Random Post Loader