I love this idea! Thanks.That's awesome! I was wondering the same thing. I bought some nice paper and stamps to write them thank you cards but most of my letter writers were professors. As such, I'll probably buy them trinkets or mugs to put on their desk that reflects their research. Example: I worked in fruit fly lab one summer so I want to buy her a mug and stencil a Drosophila on the side.
I love arts and crafts.