I'm happy to announce that I've made osCommerce 18.104.22.168 Responsive and have converted it to HTML5.
I'll welcome anyone who is interested in participating in this project as I do believe that it has huge potential but needs some tweaking and at this point I'll welcome any feedback, suggestions or advice.
I'm sure that there will be persons who would be willing to use my version and will assist with further development.
The reason for this project is so that it can be a good starting point for someone looking for a responsive store. Bare bones vanilla install with some (actually minor) modifications.
I have this project on Github: github.com/mommaroodles/responsive-html5-oscommerce
and there is a demo here: responsiveoscommerce.webwolf.co.za
I would suggest that to test the site you should use Malte Wassermanns Responsive Design Testing Tools lab.maltewassermann.com/viewport-resizer/ - create the bookmarklets see how how the site behaves.
There are issues I'm working on - table on the product_listing.php may need to be re-written in order to get it responsive.