Shane Gowland

This plugin adds support for Topic Thumbnails with bbPress. It works by retrieving the first image from each topic and displaying it alongside the topic title on the index page. Thumbnails are sized according to the default ‘thumbnail’ size in your WordPress media settings. The images will also resize appropriately if you’re using a responsive WordPress theme.
This plugin works with GD bbPress Attachments and most other bbPress image management plugins.
If you enable this plugin while bbPress is disabled (or not installed) it will display a warning message.

bbPress Topic Thumbnails

Provides bbPress with support for topic thumbnails.

codezag

Get Notification to your email when a new topic ( thread ) has been posted, This plugin work out of the box with bbPress 2.x .
This Plugin send the notifications to the wordpress admin email ( settings > general > Email Adress ).
Premium Plugins by Me:
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<li>
Suppa – Multi-Purpose WordPress Mega Menu : http://codecanyon.net/item/suppa-multipurpose-wordpress-mega-menu/7265033?red=codetemp
</li>
<li>
Kodda – WordPress Mega Menu Plugin : http://codecanyon.net/item/kodda-responsive-wordpress-mega-menu-/4718440?red=codetemp
</li>
</ul>

bbPress New Topic Notifications to Inbox

Send notification to the admin email when a new topic posted.

bbPress Topic Thumbnails vs bbPress New Topic Notifications to Inbox