Wow! I wouldn't know where to start! If I went back to when I was in my teens, the 60's, there would be more than a few opportunities. I started working at 14, so I already had a savings account; and as soon as I started working full time, I'd stay at home, pay rent and start using most of my extra money making investments. Microsoft stock was selling for $16 in the 60's and would eventually sell for over $300. I would know where are the big malls would be built or big housing developments and could buy prime land. The Florida Keys was hardly developed at all back then. It's one of my favorite areas; and I could purchase a big chunk of land for next to nothing. I would know about the 70's and disco music...I'd know the songs that hadn't been written yet, the fads, the dancing. My family, if they would believe me, could get in on all of this.
I would love to have started Facebook when the internet was in its infancy; but it would have been very hard to set up a website back then! You could be one of the first people to have a website!
What would you do?