Technological advancement. I would make much more money from that than a billion dollars...iI would then use that money to buid my own private city. Once I had 60,000+ people, I my city would become it's own state. This would be a true utopia city and technology would about such as automated cars, (Which just takes magnetic strips, gps trackers in every care, a complicated virtual network server, and software in every care that would be controlled at the central hub.), an almost perfect sewege system, a perfectly clean source of energy, vacuum tubes for transport of people throughout the city because that is just fuggin awesome, etc.
I could do more with a billion dollars than just about anybody on the planet...getting there is what sucks.
I'd make sure my parents are taken care of for the rest of their life. I'd travel...buy me a new truck...and a lambourghini...always wanted one..lol. I'd set aside several million in an interest bearing account so my kids and grandkids could access it when they retire. I don't want to raise lazy kids..they'll know the meaning of hard work...but, they'll get access to the money eventually. I wouldn't stop workin' either...I'd just do something that I like to do.....write country music...and get paid for it.