Vincent Mimoun-Prat

This plugin will allow you to easily insert panoramic pictures inside your posts using one of the best free java viewers available: PTViewer. Just insert a quicktag specifying the image and information about the panorama (field of view, image size, horizon position) and the plugin will compute the corresponding obscure applet parameters (in particular for partial panoramas covering less than 360 degrees of field of view).
All the instructions for installation, the support forums, a FAQ, etc. can be found on the <a href="http://www.marvinlabs.com/products-and-references/wordpress-addons/wp-ptviewer/" rel="nofollow ugc">plugin home page</a>.
This plugin is available under the GPL license, which means that it’s free. If you use it for a commercial web site, if you appreciate my efforts or if you want to encourage me to develop and maintain it, please consider making a donation using Paypal, a secured payment solution. You just need to click the button on the <a href="http://www.marvinlabs.com/products-and-references/wordpress-addons/wp-ptviewer/" rel="nofollow ugc">plugin home page</a> and follow the instructions.

WP PT-Viewer

A plugin for wordpress which allows you to easily insert dynamic panoramic pictures inside your posts using the java applet ptviewer.

NoSta

Fabian Stanke

This plugin is a rewrite of a JavaScript snippet called PhotoNav. It provides for easy integration of panaorama pictures in a WordPress page throught using shortcode. The user can “rotate” the view of the panorama by moving the mouse over the image area or dragging the image. 
Additional features include an integration with jQuery Colorbox and animated scrolling.
Further reading:
<ul>
<li>Suitable panorama pictures can be created e.g. using the <a href="http://hugin.sourceforge.net/" rel="nofollow ugc">Hugin</a> panorama photo stitcher</li>
<li>For usage examples and documentation, please visit the <a href="http://fmos.at/wp-photonav" rel="nofollow ugc">plugin page</a></li>
<li>If you are interested in contributing, feel free to branch on <a href="https://github.com/fmos/wp-photonav" rel="nofollow ugc">GitHub</a></li>
</ul>

WP-PhotoNav

Provides a scrolling field without scrollbars for pictures with huge horizontal dimensions. Especially useful for panorama pictures.

WP PT-Viewer vs WP-PhotoNav