roganty

Set a default thumbnail using either an image from your image gallery or use your gravatar for posts with no thumbnail set.
This plugin requires your theme to have support for post thumbnails enabled. 
Although no extra code needs to be added to your theme, some alterations might be required for trouble free usage.

Default Post Thumbnail Image

Set a default thumbnail using an image from your gallery or use your gravatar for posts with no thumbnail set

Mario Peshev

DevriX

DX Delete Attached Media

Does exactly what its supposed to do. Been looking for a plugin like this for some time.

Great plugin

Automatically deletes attached media from posts and custom post types added via the Media button.

Default Post Thumbnail Image vs DX Delete Attached Media