Does anyone know of an easy method to offer free shipping on select items but not on others?
 
Thanks in advance.

I think you can try to play with items weight in the way described at http://www.viart.com/free_shipping_coupons_and_download_products.html

I also mentioned this (limitation). I think it needs a better way.

The workaround mentioned above is for downloadable products. I want to ship some real products in a box with free shipping as a purchase inducement.