Anything that can go wrong, will; at the worst possible moment.
An example of Mrs Murphy's law:
Your driving to work and your running late.
Not only do your brakes fail, but you have just made it over a hill, and it's a long way down.
Your design project that counts for a third of your year 12 subject score is almost finished after 13 weeks.
Not only has your computer died and refuses to start again (even in safe mode!) you where only 5 mins off printing it out and handing it in later that day. There are no extensions!
Auld wan in pink who does mad poetry at Electric Picnic, tells stories in mad places and does the matchmaking at the Father Ted Festival. Mad buzzer for an auld wan.
Saw Mrs. Nellie Murphy spinning yarns at The Bog Cottage when I was off me tits.
The hypothetical man (often a sinistercharacter who decided not to go to boot camp) that is doing your girlfriend/wife while you are on deployment overseas.
Ain't no use in goin home,
Jody's got your girl and gone.
Ain't no use in goin back,
Jody's got your Cadillac,
Ain't no use in feeling blue,
Jody's took your checkbook too.
The ability girls and women have developed to hold several items at once in one hand. The skill has been developed due to the lack of pockets in women's clothing.
I thought she'd need multiple trips to carry her phone, keys, wallet, and Starbucks to her car since she needed the other hand to open the door, but she used her impressive girl grip to carry everything in one hand.