I am trying to do the same thing, and have not had any luck so far.
I have a customer who has a very short list of products in 3 different categories. I am trying to make a product listing page that shows all of the products on one page.
Here is what I am trying to do:
http://www.coquitodesigns.com/test/index.php?main_page=index&cPath=1
For a temporary fix, I created the index by hand, but if the customer wants to add more products, obviously the list will need to be updated. This is not ok for a customer that knows nothing about html code.
Since I am not really using the product_listing module, I thought there would be a way to modify it to strip away the image, price, etc.. and only display the product name. But this would only work for one category at a time.
Any ideas on how to get this to work for all 3 categories at the same time?