If I was given $1 million dollars with the stipulation that I had to spend it in one day, I would pay off all of my boyfriend and I's debt. Our parent's debt too.
Then, I would buy whatever I need to get my project car finished, followed by whatever my boyfriend needs to finish his project truck.
I'd get my kitty a bigger cat tree, the dogs some nice dog houses that work in the summer as well as the winter with keeping them cool/warm. All of them would get lots of treats.
A nice big dinner would follow, after which I would announce that the remainder of the money (if any,) was going to several different charities for military families, animal shelters, toys for tots.
I would sleep good that night. :)