For example, in Skype conversations you use emoticons. I might use (headbang) after a phrase to express frustration, or I can have a (facepalm) moment, or I can write a joke and add (rofl), etc.
But how do you do this in a technical book (not an animated book)? Not all people might understand what (rofl) stands for. So what alternatives are there, or what techniques to use to express feelings or emotions in a technical book (not one with characters where you might make the characters behave in a certain way that express the feeling/emotions)?
Just an example: a project management book or something. Where you might describe a techniques that drives everyone crazy and never gives good results, but somehow doesn't stop people for using it again and again. For that I might use (headbang).