Pat Hawks

CAYdenberg

[catthumb id=”CategoryID” link=”true”] will find the most recent post in the specified Category with a featured image and return the thumbnail for that image. If link=”true” is specified, the image will link to the category specified.
You can optionally search custom post types with the <code>post_type</code> attribute, and specify the thumbnail size with the <code>size</code> attribute. IE <code>[catthumb id="CategoryID" link="true" post_type="restaurants" size="full"]</code>
The plugin will only search featured images, not attached images. It will not look for images embedded in the post itself, or other attached images. If a category does not have any posts with featured images, this plugin will not return a thumbnail image, even if the category has posts with attached images.

Category Thumbnail

Adds shortcode [catthumb] to embed a thumbnail image for a category.

dirtysuds

Will embed a PDF file using Google Docs Viewer 
Simply include the URL for a PDF document on it’s own line, or wrapped in the embed tag like <code>[embed]http://example.com/file.pdf[/embed]</code> and the plugin will embed the PDF into the page using the Google Docs Viewer embed code. 
The url must end with <code>.pdf</code>
Supported attributes in the embed tag are <code>class</code> <code>id</code> <code>title</code> <code>height</code> and <code>width</code>

Embed PDF

Adds pseudo oembed support for PDF documents

Category Thumbnail vs Embed PDF