This Widget shows up to five random posts from a given category
Installing is pretty easy takes only a minute or two.
Upload 'random-one-cat-widget' directory to your '/wp-content/plugins/' directory.
Activate the plugin through the 'Plugins' screen in WordPress.
On the 'Widgets' sub-menu of 'Appearance' you will find a new widget type called 'Random One Cat'.
Add one or more of these to your themes widget display areas.
For each widget you add, select a title and category, then decide how you'd like to see the title or custom fields.
Save your settings.