WP-SMF-Bridge is a simple user registration and logon bridge between WordPress and Simple Machine Forum. To get this working, it is highly recommended that you have a fresh, unmodified install of SMF 1.1 or higher installed and running alongside an install of WordPress. It must be installed in a subdirectory under your WP install and should not be being accessed through a sumdomain. For example, if your website’s address is mysite.mydomain.com, your forums should be somewhere like mysite.mydomain.com/myforum. Also, WordPress must be able to access your SMF configuration files, otherwise it won’t work!
Please do keep in mind that this is a new plugin, and has not been thoroughly tested yet – and should probably not be used on a production website! I am not responsible for any data loss that might occur through your use of this plugin! Please see the plugin’s website for a bug-tracker and bug reporting system! If you find a problem, let me know about it so that it may be fixed. If you want to see a feature added, let me know about it so that I may add it!

SMF Bridge

User registration and login bridge between Wordpress and Simple Machine Forum

Edward Caissie

Plugin with multi-widget functionality that builds an SMF Forum RSS feed url by user option choices; and, displays a SMF forum feed. The widget includes the additional option to include in the feed: specific boards and/or specific categories. There are also check boxes to include the feed item date and the item summary, too.
NB: If updating from a version before 1.1 please make sure to re-save your widget options (check your feed type) for each instance after upgrading. This will set the feed type correctly using the new feed drop-down selection option. Thanks! ~cais 
* Copyright 2009-2015 Edward Caissie (email : edward.caissie@gmail.com)
This program is free software; you can redistribute it and/or modify 
 it under the terms of the GNU General Public License version 2, 
 as published by the Free Software Foundation.
You may NOT assume that you can use any other version of the GPL.
This program is distributed in the hope that it will be useful, 
 but WITHOUT ANY WARRANTY; without even the implied warranty of 
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 
 GNU General Public License for more details.
You should have received a copy of the GNU General Public License 
 along with this program; if not, write to the Free Software 
 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
The license for this software can also likely be found here: 
 http://www.gnu.org/licenses/gpl-2.0.html

BNS SMF Feeds

Plugin with multi-widget functionality that builds an SMF Forum RSS feed url by user option choices; and, displays a SMF forum feed.

SMF Bridge vs BNS SMF Feeds