LordPretender

<p>This plugin allow you to add files into your media library without having to upload them. So, you will be able to share, for example, your files into your Google Drive.<br />
This also save you steps to download the image to local computer and upload again to your own WordPress.</p>
<h4>Features</h4>
<ul>
<li>Automatically downloads and adds the file to the media library.</li>
<li>After the uploading is successful, you are redirected to the edit screen</li>
<li>A new dropdown list is available in the media library to let you display only uploaded files, not uploaded files, …</li>
</ul>


Add Media from URL

large chunks of code taken from the much better original here:

https://en-au.wordpress.org/plugins/lh-add-media-from-url/

IMO it unethical to use this plugin

A crappy clone of the original

Let you add media files into your media library without having to upload them.

dalziel

<p>Provides the ability to have a bookmarklet on your browser that will let you add any page as a link on your blog.<br />
Replaces the functionality of the Add Link bookmarklet that was removed in WordPress 2.5.  For more information<br />
on what a bookmarklet is and how to use them see <a href="http://www.bookmarklets.com/" rel="nofollow ugc">bookmarklets.com</a></p>


Link This Bookmarklet

Provides the ability to have a bookmarklet on your browser that will let you add any page as a link on your blog.

Add Media from URL vs Link This Bookmarklet