Friend of mine had a perfect day today:

It's 3am, you're coding hard, can't even see properly, but you know only a two or three proper lines and you are finished. A few minutes later you set your pc to hibernate because you can't go further and go to sleep.

In the morning/noon you log in, see only a mess. Half of the new variables are probably obfuscated or in some alien language because you can't read that shit and a cherry on the top - 1/4 of a _big_ test suite reports errors. What a lovely day.