In my personal experience, I first heard of it 1 year ago in a online forum game, people sold gold for Bitcoins, around March, gave it no importance at first. Now im kinda utterly commited to it. Really an interest subject of study.
I heard about it while searching for a way to exchange my PSC to Paypal (or something like that) which lead me to this forum and this was on the start of 2014 however I wasn't really interested , but with time ... I found my self on videos about Bitcoin on YouTube while I was Youtubing something about Paypal then I got interested and here I'm .
Heard about bitcoin from a friend and that also told about this community.