Well, I'm not going to do this, because everyone I know would either think it was crazy to write and mail a paper letter or feel oppressed by the implication that now they need to handwrite a letter.
But I do still use handwriting, and I often prefer it when I'm writing notes for my own private use — that is, not composing something for readers. I prepare for class by writing notes in the margin, and I teach the class using those notes along with the assigned text. I feel that the handwriting has a spirit to it that helps me a lot. It's not something I use to show my personality and feeling to another person, though I understand why handwriting conveys that. It's something that, for me, remains more closely interwoven with my continuing thinking about a subject. It's less final and it works better to keep me connected with the original text. Marginalia — it means a lot to me.