Definitely something that always existed. I was always behind the tech curve anyway. I got a NES Christmas of '90, got a Super Nintendo about the time Chrono Trigger came out, got a PSX by the time FFVII had gone Greatest Hits and systems had dropped to $100, and so on.
I had a very limited selection of games as a kid, but I was pretty discerning, especially with quite a few trusty Nintendo Powers at my side. Of course, that always meant I had a running backlog of games I eventually wanted to try out.
So about the time I hit college, I got my first PC, and emulation was really starting to take off. The best thing going was VGB-DOS, but that was about the time Nesticle came out as well. Needless to say, all those games I had missed out on were getting tried.
Of course, that's never enough. I still pick up good carts when the prices are reasonable, and I went on a eBay run to re-obtain the games I had traded away as a kid. So while my current library isn't super-impressive, it's still over 200 games strong on the NES side! I'm proudest of my complete copy of Dragon Warrior IV.
I still play modern games, but I gravitate to the old-school, unquestionably. And when games tap both into the modern and the retro, it's a good day all the way around.