Taking a crap is probably one of the most Zen like things you can do. Unless you ruin it by taking a magazine or newspaper with you to read. It is a time to zone out with nothing to focus on except your own bodily function – no counting breaths, no reciting koans and no chasing the monkey-mind: just sitting quietly and experiencing the moment.
The Buddha became awakened after seeing a beautiful girl, tasting the refreshing quality of water and eating a bowl of rice. Buddhist text doesn't say so, but I am sure later that evening he totally zoned out taking the first good crap he had had in many months.
It is rewarding how simple bodily functions can bring so much contentment if you can stay focused in the moment.
Perhaps this is more than you would like to know: but sometimes I err by trying to name my craps – usually after a Republican Congressperson. It takes me out of the moment and is totally unrewarding. I find the rest of my day lacking in tranquility.
Like a sexual orgasm, taking a crap is a personal experience, and if you are not focused in that moment you miss out on a great happening that can never be reclaimed.