Highlighting a portion of an image.

I found an article on techzilo.com ( via digg.com ) that showed several desks with Macs. Some of the photos in the article had a highlighting technique that seemed very desirable to learn. When I hovered the cursor over parts of the picture, an item within the shot would be encapsulated inside a white rectangle. Then, a yellow box with an explanation would appear that explained what was within the highlighted rectangle.

I am sorry for not being able to explain this better. Hopefully someone here will know what program is used to do this. I checked through iPhoto but couldn't find anything.

I wanted to do a screen capture on one of these images but the article is no longer available.

This can be done with image maps & javascript or more likely, as it's so popular at the moment, Flash.