They say that no man has ever assembled a computer fully, and had it turn on fully working the first time. Whoever claims to have done this is a liar.
I've had many 5 minute "This shouldn't take too longs" turn into several hours of anger, frustration, and eventual defeat, especially with my older computers being stupid.
Probably the biggest instance of Murphy's Law I've had is while I was giving the first attempt at building my Pentium Pro computer about a year ago.
I got the board, DOA. Nothing worked, and I spent hours trying to get it to do anything. Then, after a day of wasted time and frayed nerves, my only capable machine, an i7-4790k box, the board popped. No big deal, it's under warranty, except the warranty doesn't cover complete jackasses who forget how to install an LGA socket cover, resulting in me having a nice MSI-Z97 PCMate board with a not so nice LGA socket, and no way in hell I'm getting a new one.
b r i l l i a n t
This doesn't end, oh no, because despite me having to slap together an Athlon 64 X2 5000+ (yes, that was my second best machine) into my machine to have my SSD probably being smacked to hell and back with memory swapping (it's still here, though), I had to go on vacation the VERY NEXT DAY.
b r i l l i a n t
So I have to leave returning the Socket 8 board to someone else, since I was going to be gone longer than I would be willing to wait for that sort of thing. The vacation went alright, despite knowing I had to buy a new board when I came home, all the while suffering with a CPU and board from 2006. I come home to find my keyboard's (musical) LCD had fractured (the readout that shows all the instruments and such). So, after all that stupidity, I have two broken boards, a crippled workstation, a broken keyboard, and I'm out 80 bucks for a new Z97 board.
b r i l l i a n t
friggin Murphy.