Like seemingly every teenager in Ireland, my daughter has a mobile phone. Of course, she loves sending and receiving texts.
What she isn't as fond of is that her father loves sending texts too. I use the web to send her texts for free. What she really hates is that I have been using text messages to send her math problems. Math's not her favorite subject (it was always mine, which is why I majored in it in college) so we do a little extra work when we can. I send her the problems by text so that she can have them done before I see her later in the evenings.
Math problems by text - you never see that in any ads for mobile phones. If this became common practice, it would probably cause a collapse in the teen-dependent mobile phone market.