Liquidesign sells them, but you can easily do it yourself!
resource: http://www.designflowid.com/bagalight.html
Use the paper bags that you can get in almost every super market and bring an impressive value to these every-day items.
Cut a shape of your choice in the paper bag, put a colored cellophane paper on the inner surface and place a tea light inside.
Now you can enjoy your very romantic and customized BAGALIGHT.