Lentil

If you use Gallery2 in an external (non WPG2) installation, you may want to display images using the Gallery2 Image Block module. If so, this is the widget for you. Options described in the <a href="http://codex.gallery2.org/Gallery2:Modules:imageblock" rel="nofollow ugc">Gallery 2 Image Block</a> documentation are included, but not all have been tested. Your mileage may vary.
User configuration of Image Block options is available through the Widget configuration panel. Blank (empty) options use the Gallery2 defaults.
Note: The widget is written using <a href="http://www.php.net/curl" rel="nofollow ugc">lib_curl()</a> to avoid url_fopen issues.
For more information, see the <a href="http://www.theschierers.net/blog/g2-imageblock-plugin" rel="nofollow ugc">plugin page</a>.

External Gallery2 Image Block Plugin

Widget to display a Gallery 2 (not WPG2!) Image Block in Wordpress sidebar

cb2206

WP-Gallery-Remote includes albums and images from any Gallery installation using Gallery?s Gallery Remote Protocol. Images are display as thumbnails in you posts and pages. Thereby you can choose between a plain output of the thumbnails and a CSS and Javascript based carousel mode. Have a look at the screenshots to see how that looks like. 
If the <a href="http://www.m3nt0r.de/blog/lightbox-wordpress-plugin/" title="Lightbox Plugin" rel="nofollow ugc">Lightbox Plugin</a> is available and activated, clicking on a thumbnail opens the respective image using the lightbox effect. If the plugin is not available or activated, the image is shown in a new browser window.
Features
<ul>
<li>displays images and albums of any Gallery installation which has enabled the Gallery-Remote-Protocol</li>
<li>support for multiple wpgr tags in one post/page (v1.1)</li>
<li>support for multiple Gallery installations (v1.2)</li>
<li>two output types: plain and carousel (v1.2)</li>
<li>Lightbox integration</li>
<li>supports caching of fetched album and image meta data (can be enabled/disabled globally and per post/page)</li>
<li>include/exclude filter to only show some images from an album</li>
<li>global and per post/page options to display album title and subalbums</li>
<li>uses Gallery?s image captions</li>
<li>uses CURL or CURL emulation (v1.4)</li>
</ul>
<h3>License</h3>
This program is free software; you can redistribute it and/or modify 
 it under the terms of the GNU General Public License as published by 
 the Free Software Foundation; either version 2 of the License, or 
 (at your option) any later version.
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.

WP-Gallery-Remote

Allows to integrate images from any Gallery installation (http://gallery.sf.net) into your posts/pages.

External Gallery2 Image Block Plugin vs WP-Gallery-Remote