Plugin/hack to easily add image link to other sites

Hi Everyone,
I’m currently working on a site called Kinect Hacks.

Here is what I am trying to do. On the site, sometimes we will be referencing source code for who came up with the hack. I want to have a spot in the control panel where all you have to do is paste the link in the field that you want the image to link to and then when you save it, the image will appear on the post and link to what you pasted in the control panel.

Are there any plugins that can help do this?