Pictures Listing

Here a question.
Lets say I have a site called:

http://www.chupaelcabezadelapiz.com

and in here I create a folder:

http://www.chupaelcabezadelapiz.com/suckitgood/

In this folder I put 10 pictures example a.gif to j.gif
and I create an index.html to show ONLY SOME of the pics.

When I open

http://www.chupaelcabezadelapiz.com/suckitgood/
I see the pics I have listed in the index page.

The question is can someone get to see the other pictues I have
in the page if they do not know the name of the pics?

Is there any piece of software that would list the content of the "suckit" folder?

Thanks