I could think of a list of albums, but no doubt it'd inadvertently turn into one of those top 10 most important albums to you lists, so I won't bother. I can literally pin down one moment and two songs that basically changed my life though...
^ I was on the way back home from school in a taxi one night (I think it would've been 2000/2001 or something), the driver had Virgin Radio on and, in the 10-odd minutes before I was dropped off back at my house, these two songs played back to back. I'm sure a few of us remember Kazaa (an older form of Limewire for those who don't), but I loved what I heard and downloaded both those songs that same evening. It might have taken a few years longer, but these two songs basically changed my approach to music, and thus a very large part of my life, completely.