I have and now I'm going to show you how to do it yourself.
First open up GIMP. If you don't have GIMP, then get it from here.
Sorry the video is choppy and a little blurry.
Step 1: Open Up the Image in GIMP.
Step 2: Duplicate the Image.
If your Layers menu isn't open:
1. Click File
2.Go to Dialogs
3. Click Layers
Or do Ctrl+L
Step 3: B&W
To do this:
1. Go to Colors
2. Click Colorify
3. Click the white box.
4. Click ok.
Step 4: Making the Color Detail.
I decided on this rainbow picture, but I didn't know the rainbow would cause a problem.
Step 5: Use the Eraser Tool.
1. Choose the Eraser tool.
2. Color the area you want.
Once again, this is where the rainbow came to be a problem for me.
Step 6: Saving
The File menu to save the picture is the picture window. Not the GIMP window.
Step 7: You're Done!!!
Below is another picture I did that demonstrates this better.
Pictures: Courtesy of Google