If you're anything like me, then in this modern world of email and texting most of your friends will be reduced to single letters when signing (mostly electronic) communications.
I tend to sign most of my informal emails with "D." rather than writing "Dan" at the bottom of them.
But the problem is, I know too many people whose names begin with the same letter. J and M are particularly troublesome.
I've one friend for whom "M" became almost her official name. Even when referring to her in emails, we'd call her "M" rather than typing out her full name. But now I have a couple of other people who sign themselves "M" and it just doesn't feel right.
"J" is even more of a problem. My significant other signs things with a "J" but I also have other friends who sign things with a "J" too. When they do it on Christmas cards (for the single letter signing is not always limited to electronic media) it's obvious because I recognise the handwriting - and in the case of my significant other, the card is handed to me in person, of course. But when it's an email, there's no flourish or other artefact to tell me who sent the email. Of course, I could look at the email address at the moment, but there's the fun in that.
Some people pimp their mongrams with punctuation - " \\\J" or "D..." or "K**" or "Wxx" (I made most of those up by the way) - which gives it a little more individuality.
It's interesting to note the kinds of people who sign with a single letter, and those who sign with their full name.
For some people, it's a sign of informality and a friendly relationship to get an email signed with a single letter. For others it's a sign that they are using their Blackberry and can't be bothered to type more than is necessary. It's an interesting exercise, though - just scan your emails and see who signs with their full name and who signs with something a little less formal...