my boyfriend's mom found this tip in Food & Wine magazine, and it's incredible:
Instead of using regular old salt on your edamame, grind up some lapsang souchong tea with a little bit of salt and sprinkle it on. a nice smoky version of an already delicious snack!
I've also used a smoked salt which has a similar result. I buy smoked salt at Rainbow Grocery but I've seen it at whole foods as well.