macmiller

The plugin is intended to create a number of links which you can display on your wordpress page. Each link represents a recent post to the phpBB forum. Clicking on a link will take you to the associated post within that topic on the phpBB forum. There are a number of parameters which indicates how many items should be returned and the length description.
The returned item will look like: 
* <code>POST TITLE(number of replies) in TOPIC TITLE on DATE TIME</code>

phpBB Topics Portal

A widget that accesses your phpBB forum and displays recent posts on your Wordpress page.

skipstorm

This plugins adds a widget with the latest posts from your phpbb3 forum. 
To make it work you have to add a file on your forum directory wich is easily configurable to fetch the posts from a specific category or the whole forum. 
This plugins supports multiple istances so you can display topics from different forums or categories in multiple widgets.

Sk Latest Post Widget

This plugins adds a widget with the latest posts from your forum.

phpBB Topics Portal vs Sk Latest Post Widget