By Yahoo! Launch Cast.

I signed up for the free version.
I play it while at work and at home - am at the computer for endless hours everyday so it was an unlimited supply of favorite songs/bands/albums along with brand new stuff I'd never heard of but that (because of how I rated other songs/bands/albums) Launch was suggesting to me. Launch was predicting and catering to my tastes almost perfectly. They'd bust out with new bands and I loved the vast majority of them. I wanted unlimited skipping. I wanted better sound quality. I wanted more features.

I upgraded, paying for Launchcast Plus.
I went crazy creating mood stations and finding out all I could about new bands Launch was suggesting to me. Looking up their websites and discographies and tour information. Armed with better sound quality and unlimited skipping I was listening to my Launchcast Plus station even more. I'd leave the window open on both my computer at home and at the office 24/7, pausing it when I was away from the computer and starting it back up again when I was back.
I've completely abandoned downloading songs. I downloaded music very rarely anyways, but would still on occasion snag a single song here and there if I knew nothing else about the band or wanted nothing else of theirs. But now I've deleted KazaaLite from my computer at home because I have no use for it. Launch has more variety than my mp3 collection and, unlike p2p, Launch feeds me new shit I end up liking rather than me having to go find stuff or only get stuff I've already heard.

I started buying albums of bands Launch introduced me to.
About 20 so far. All kinds of albums. Mostly from bands I'd not even heard of 3 months ago. Some of bands I already knew but who I only listened to a few songs of. Some of bands I knew all about but had never gotten around to ordering CDs of.

I started checking concert listings and tour dates and buying tickets.
Now, I've always done this. I go to quite a fair number of shows every year to see alltime favorite bands. But now I'm going to all these shows of bands I'd never heard of a few months ago but now can't wait to see live. Timing only allows for a couple of these shows so far but I'm keeping an eye out for plenty others incase they come to Southern California. And Launch is giving me so many smaller, lesser known bands that there's a countless supply of $5-$20 shows here. Not just $100 2 day festivals but bands Launch introduced me to playing at clubs up in Hollywood and what not for cheap ticket prices.

Yes... I am Launchcast's bitch. And I'm loving every bit of it. Launch is a work of genius. Not just because it's so addictive and user-friendly and quite the remarkable service that's entirely won me over, but because it's just really, really, really fucking cool. It very well is my new favorite Internet thing.