Magic Online made it possible for me to play vintage.
I've been playing Magic for about 10 years now and older formats have always grabbed my interest more than modern or standard. I found vintage my first year of college and just started watching videos and it immediately became my favorite format without even playing it. I played a lot of proxy games against friends and fell in love with the format.
A few years later Vintage Masters had been released and I had enough money to buy into vintage on MtGO and never looked back.