andreyk

Use this plugin instead of tiresome saving images from the internet and uploading them to your blog. You learn the value of this grabber e.g. when you need to move your old non-WordPress site with many pictures to the WordPress-based. 
The plugin recognizes images by the presence (jpg|jpeg|gif|png) in URLs.
If you like this plugin please vote for it.
Please feel free to contact me with your questions or suggestions.

Remote Images Grabber

Fetches images from an URL or a piece of html-code, saves them directly into your blog media directory, and attaches to the appointed post.

pekastel

Lets you pick a Creative Commons picture from Flickr and use it anywhere you want on your WordPress installation. The plugin will maintain attribution to the original Flickr author to keep peace with the CC Attribution License.
This plugin makes use of the newest WordPress 3.4 feature that allows to embed html in image captions, and also is backward compatible with older version of wordpress as well.
Features:
<ol>
<li>Search photos from flickr with creative commons license by tag (since version 1.2 you can search by any type of license)</li>
<li>Preview image results.</li>
<li>Define the order of the search results.</li>
<li>Automatically add image caption that links back to the original flickr owner.</li>
<li>Lets you use the standard features provided by WordPress for image editing:
<ul>
<li>Image alignment.</li>
<li>Cropping.</li>
<li>Rotating.</li>
<li>Flipping.</li>
<li>Resizing.</li>
</ul>
</li>
</ol>

Flickr – Pick a Picture

Lets you pick a Creative Commons picture from Flickr and use it anywhere you want on your WordPress installation.

Remote Images Grabber vs Flickr – Pick a Picture