Irritation. According to the definition of enlightenment, irritation in its bigger form will not disappear until a person is on the third level of enlightenment. In its more subtle form, it does not disappear until a person's fully enlightened. Maybe it's just idealism that you think you shouldn't get irritated, but the subtle stuff does bother a lot of meditators. The gross stuff isn't so bad anymore, but the subtle stuff still is.
The first computer book I think I ever read was written by a fella who had been a telephone computer helpline guy; he was on the end of the telephone and if you called up and needed some help, he would help you. In the book, he talked about how people would get so frustrated with their computers. They would get crazed, yelling, "My computer won't work! It just won't work! It won't come on! It won't come on!" He would ask, "Is it plugged in?" He said that fixed 50% of the problems! How often do you get the message on your computer, "Can't find the printer"? "It's right there! What do you mean you can't find it!" This gets to people, even to people who have let go of the big anger towards somebody who takes their sitting mat in the hall. or people who take four pieces of pineapple, like I said the other day. Those are the bigger things. But we really have to work more on these little things, too, that just kind of creep in.
If you're not working on those more subtle levels of Dukkha, if you're only reflecting on the bigger Dukkha, then also reflect on the little stuff. Try to remember all those little things that don't quite work right, even in some of the toilets that you flush. Some toilets here flush. Some don't flush; you pour the water in yourself. But with a flush toilet, sometimes when you push the handle, it doesn't work right. How often can you see a little irritation just come up? You have to press it a second time. In the airport, in particular, some of them just don't work right. Little things, little things. If you feel you want to work more on irritation in general, start trying to think of the little things.