The program is, as I said, very simple. The program eases the creation of image archives, or in other very similar words, images that contain archives. It isn't slick like steganography. Its pretty much just an image file with an archive stuck to the back of it.
The program does also, optionally, shrink the image and stick a little icon on it to indicate that it contains an archive. Had to have some excuse for its existance.
Why, you may ask, would anyone other than illicit pornographers need such a tool? Well, as I said, its not steganography. Its pretty obvious when your 128x128 pixel image of tacgnol weighs in at 1.2 gigs that you're hiding a porno ISO inside of it. Of course, a stego'd pic would be just as big... I'm getting away from the point.
You may find yourself on an imageboard or other discussion forum that allows its users to upload images but no other type of content. If you have a need to upload other content, ImageRAR is for you. Simply zip up your content, stick it in an image of your choice, and upload it on the server for great lulz.
I shared this before, and got some complaints about it. Having it up on CodePlex will allow users to register feedback, which transforms into work items that I can use to improve the code. It also lets the paranoid see what's in the program so they know I'm not trying to format their hard drive.
Anyhoo, check it out if you're incredibly bored sometime.