The idea is to create a mix between old letters and emails. Yes, we have HTML emails, but you have to save the images on a server, people have to download the images, size is not always right, compression kicks in, etc. Nah. Too much trouble.
Better to send out a PDF with your own signature and letterhead, like grandpa used to before we messed it up with this whole e-mail mumbo jumbo.
Something I'm working on. Still need some cleaning but, works for me. I hope to start a trend among my friends.