Here is my work in progress on the 3DNES version of Super Mario Bros. Here is the 3dn file download:
https://drive.google.com/uc?export=download&id=0B7...
Put the 3dn file in the same location of your rom and name it the same name as your rom (Ex: mario.nes = mario.3dn), then open up 3DNES and play!
Feedback would be greatly appreciated!