There are a number of email programs that allow you to leverage technology in order to personalize your messaging. (entrepreneur.com)
While the space available in most email programs or via smartphone mail is around 60 characters, when opened your space in this field will typically expand to around 148. (blog.simplyhired.com)
Even used in the body of the message, it can help, since many email programs give the reader a short preview of the message. (lawyerist.com)