William P. Davis

This plugin allows you to duplicate images you have in the media library and attach them to a new post, rather than having to create a new copy of the image and upload it to WordPress again.
It works by copying the post and its metadata. It does not actually copy the image. Any changes you make to the new copy of the attachment — updating the caption or cropping, for example, will only be applied to the new attachment, not to the original.
This is useful if you query posts for its attachments to display photos, or if you make use of galleries and have old images you might want to include, among other things.
To use, go to the Library tab in a post. You should see an ‘Attach’ link.

BDN Duplicate Images

Allows you to duplicate images in the media library and attach them to the current post.

OriginalEXE

If you were ever annoyed about the way WordPress handles images resizing, this is a plugin for you.
What this plugin does is it optimizes the image handling in such a way that images are resized only when they are actually needed. What that means is that if your plugins/theme define a lot of image sizes, none of them will be generated on the image upload (like they would be usually), but only if they are actually requested in that size.
Resizing is done only once, images are later normally served by WordPress, so there is no performance hit.
Plugin also includes a method for removing all of the previously generated image sizes (useful when you install this plugin on a site with a lot of existing media).
TO REMOVE image sizes generated prior to activating the plugin, visit the ‘Tools -> Remove image sizes’ and use the button to perform the cleanup.
Other than that, you don’t need to do anything, plugin works silently in the background.
To sum up:
<ul>
<li>Resize images only when needed</li>
<li>Clean up existing images sizes</li>
<li>No performance hit</li>
<li>Free up your hosting space</li>
</ul>

Optimize Images Resizing

Hello! nice plugin one click option and all done!
add a custom search for images to detele.
ex. -unsmushed.jpg

God Job! Need More Features!

Plugin optimizes the process of generating custom image sizes in WordPress and offers a cleanup functionality for preexisting images.

BDN Duplicate Images vs Optimize Images Resizing