Sod's Law is also more universally known as Murphy's Law.
Look it up here
An example of Sod's Law for me on AB is that someone else will have posted a reply identical to my own before I've even finished typing mine.
I'm a nurse and as soon as i finish a difficult dressing the doctor will come in, and want take a look at the wound.
And then there's when i haven't sat down all day, and the second i do, the boss comes in and says 'what are u doing sitting around, if you're not busy go and clean something'
I always seem to swear when a boss is behind me too.