I try to send out email campaigns to existing and prospective clients twice a month (more or less depending on my schedule) and then follow up with a print campaign once or twice a quarter. I think it's really important to reach people with print because email can so easily go straight to the trash or spam folder and then quickly be forgotten. Many prospective clients are so busy that they don't want to receive emails at all. Getting a physical printed piece in the mail is different than getting an email, it gives an art director something to hang on to and if they really like it they might file it away and contact you for a future assignment. I usually get at least one or two jobs after I send out a printed piece so it is worth the time,money energy that I put into it.
A few weeks back I put together an email and coinciding print campaign with my "Good Bad and Ugly" presidential portraits. I usually send out a postcard but this was a much larger and more expensive mailer. The mailer consisted of four over sized double-sided presidential postcards, a note, a business card and my very own "presidential" Melcher 2016 campaign sticker. All inside a brown grocery bag stock envelope with my crossed stylus logo sticker on the back. It was a lot of work and money but I've gotten a great response from it so far. Several art directors even emailed me kudos - which was really nice. I know how freaking busy they are and taking the time out of their schedules to say that the cards brightened their days was totally worth it for me.
I created a small gallery of snapshots from the whole process. Click through it to see all of the photos and the GIGANTIC (and heavy) boxes of envelopes at the end!