I don't think music has ever changed my life in any way, but I can list 10 albums that changed the way I see music in general, and have a lot of importance to me, I hope that fits with your idea...
(Not in any particular order)
1. Tool - 10,000 Days
The first Tool album I ever heard, by accident really. But it is now linked to serveral moments in my life, some really good times, and some bad times. It got me into Tool, which eventually got me into other non-metal music.
2. Lamb of God - As The Palaces Burn
The first record I loved with "harsh" vocals. At the time I was listening to stuff like Megadeth and Iron Maiden, when one day the vocals to this record just clicked. This set me on my path to more extreme metal music, deathcore, metalcore, black metal, etc etc.
3. Marilyn Manson - Holy Wood
I would have put Antichrist Superstar, but to stick with the "nothing pre-1999" I went with Holy Wood. But to be fair, I consider the triptych (Antichrist, Mechanical Animals, Holy Wood) all of equal importance to me. When I figured out the intelligence, and incredible story telling and concept behind these three records, they became some of my favorites. I realized how much I loved concept records, and I love to pick apart the story and try and get in the artists head to see why they wrote what they did.
4. Opeth - Ghost Reveries
The record that got me in to Opeth (I think). I can't really remember if this was the first Opeth record I heard, but I do remember when I saw the brilliance of Opeth's work. Not so much of an important album musically because I had already been divulging in metal for years, but I still hold it close to me.
5. Godspeed You! Black Emperor - F#A#∞
The first time I heard this record I was blown away. I never had heard any thing like it (even though I loved post-rock before I had heard it), and it completely changed the way I looked at how music could be done. I still have yet to find a post-rock record that tops this in terms of originality and importance (to me at least).
6. Radiohead - Kid A
This record confirmed my love for Radiohead. It is such a pivotal album in music history, and really shows how modern music is thriving. This album always helps me out when i'm down, and its definitely a record I hold close to me.
7. The Mars Volta - De-Loused in the Comatorium
This was love at first listen. Another record I had never heard anything like it before. This really helped expand my tastes into more obscure and progressive music.
8. Linkin Park - Meteora
I don't think anyone who grew up in the 90's could say they didn't like this album. This was the first album I bought and loved. Of course, the last time I listened to this was in middle school, but it still played a huge part in my musical journey and what I listen to today, i'm sure others feel the same way.
9. Aphrodite's Child - 666
This record brought me into a world of obscure 70's prog that I now love. I listened to the usual artists before this (King Crimson, Yes, Camel, etc), but this record really blew me away. The concept, the music, everything about it is perfect. After listening to this I had to dive deeper into the 70's prog pool and find the most obscure artists I could find.
10. Battles Mirrored
And lastly, Mirrored. This record is insane. These guys pushing modern music in a direction that has never been explored before. I hope other artists learn from these guys, because they are definitely on to something.
Well there it goes, 10 records that have changed my musical life.
...and btw i'm pretty sure their first album came like 99 or 00...amirite? So you can't really count it into the 90's.
