Undivided Attention

Does it happen to you, too?

There is a customer on the phone, and after some minutes of attentively listening to them, your mind starts to wander. Not necessarily far away from work, but maybe you have just noticed several new emails have come in while you are on the phone, and quickly checking what it is they want from you now won't do any harm, will it?

Well.
I have noticed this more and more in myself, and I do not particularly like it.

When I get in touch with someone, no matter whether it is face to face or on the phone, I would like to think that I have the other person's undivided attention - at least for as long as it takes me to get my point across, to ask my question or phrase my problem.
So, naturally, someone who talks to me can expect the same from me.

What does it take, then, in order for me to really stick with the conversation until both parties are satisfied with whatever conclusion has been reached, and then move on to the next task at hand?

It seems that my attention span is not longer than the average clip on youtube, which really makes me sound like a very sad person.
I almost feel ashamed these days when, as it happened today, a customer tells me on the phone that he is really happy with my work for him and that I am very good at what I am doing, and that he has also told my boss last time they spoke.
He obviously didn't have a clue that, while we were talking (or, rather, he was talking and I was - sort of! - listening), I was checking and sorting the contents of several email accounts.

Some time ago, I was home in the evening and my sister called. I had already been on the computer when the phone rang, and some minutes into our conversation, I started to reply to a post on one of the forums where I moderate.
She stopped in mid-sentence, then said: "You aren't really typing right now, while I am talking to you, are you?!"
I could tell she was hurt, and rightly so. She - like anyone else who gets in touch with me by phone or in a face-to-face conversation - deserves my undivided attention. And I was not granting her that, and hated myself for it at the same time, apologizing to her and really meaning it.

Guess what - a few weeks later, I did the same thing again. Am I a hopeless case?

It is not that I am not genuinely interested in what other people tell me - I am!
With my customers, I really strive to make them happy (in business terms only, of course), and I like my job.
Face to face conversations can not always guarantee undivided attention. When a colleague is telling me about what she's been doing last weekend, this kind of conversation will instantly be interrupted as soon as work (i.e. a customer) demands we be there for them.

Maybe I need to practise more.
At home, I can take the phone away from the computer and speak without looking at the monitor. At work, this is not so easy, since I usually am required to look things like prices and lead times up for the customer as we speak.
But, with a little self-discipline, it shouldn't be too difficult to give my conversation partners what they desverve:
my undivided attention.

Helpful suggestions are most welcome. Seriously.