Have a look at the source coode for this... it's REALLY simple, and works great!.

You need to have a javascript enabled browser though.

the section between <script> and </script> is the javascript bit that "preloads" the images into memory so that they will display fast.

The section below that shows the syntax for how you do an image (I did it 7 times - sorta like you'll have to).

I just created 14 images (and typed their names on them as text - just as an example), 7 are white on black, and 7 are black on white, and put them into a folder called /images, but you can put them all in the same directory if you just search-and-replace the word "" with nothing for the whole document.