E mail is good for some things but I consider it a basic form of communication one small step behind conversation.
Just as one would thank a person for example in conversation and also send a card of thanks I would immagine in the same way one can send an e.mail but to really express yourself formally a card with personal hand written note is the way I like to be thanked. More from the heart and hand.

One way of thinking of the cards is that they help support artists. I do my own and enjoy the opportunity once a year to focus my thoughts through creativity. These days there are some very good cards out there done artistically. Check local artist studios.

I am thinking of combining music with the card next year including a cd of whistle and perhaps storytelling.

Conrad