Amarok
It wasn’t too long ago that I refused to use Amarok just because it was a KDE app and I was perfectly happy with audacious or mpd (a service music player, kinda cool, but not really practical). That was back when I didn’t listen to much music. Now I listen to a lot more, thank you discography torrents (and rapidshare links). Well, when I started this listening to a lot more music, I happened to be on windows, and I picked up an FOSS music player called MusikCube. It was a pretty good player, but of course my sessions using Windows don’t last too long, soon I was back with my beloved Gentoo and with all my music… hmm… what to do.
All of my friends who were heavy (at least compared to me they were heavy) music listeners at the time used Amarok and insisted it was amazing, I kept refusing to use it since it’s a KDE app, it doesn’t fit with my Gnome/Openbox desktop and not only that, like KDE itself it looks like a giant peice of bloatware. I messed around wth BMP and Audacious instead, never quite getting something satisfying. I tired banshee briefly but didn’t really like how it organized things, they way it sorted my music was garbage, I didn’t like it’s playlist setup either, I had to add tracks to a newly created playlist.
So, running out of options, I decided it’d be time to give Amarok a shot. I ran through it’s wonderful startup wizard, letting it make a giant SQLite DB out of my music. It had one feature that immediately made it stand out above any other media player I’d ever used, lyric fetching, more on that later. That’s what was most of what made me interested in Amarok in the first place. I let it import all the music I had (1 discography and a few single tracks, yippeee). At first, I found the amarok UI to feel both empty and bloated. Too many buttons on half of it and a very blank playlist all over the rest. Despite my initial hatred for it’s UI, I quickly grew to love it, I hid the useless options about media devices and “Magnatune” and started enjoying it’s library, I fetched the covers for the albums I had and moved the OSD to the bottom right (I’ve since gotten a script that allows me to use libnotify with Amarok). Another thing I fell in love with was amarok’s playlist features, this I’ve seen in no other media player to date. I can right click on a song on the playlist and do things like “queue as next”, “stop after track” and rearranging my playlist takes half a second, this making is superiour to MusikCube and Banshee.
As for the lyrics part… Last time I had that was when I used WinAmp on Windows ages ago with EvilLyrics. Unfortunately the built in lyric grabbing was pretty crap, but it got 1/2 my songs, I think /to myself: “hmm… something about lyric scripts, I’ll do that one day”. I’m now the author of a fairly popular Amarok plugin called Googlyrics. I took the idea from EvilLyrics: Google for lyrics and then rip them off major lyric sites. A little perl WWW::Mechanize (oh, python rewrite coming soon!) glue and all was good, a lot of regex writing and there’s some progress 
So, not only did I go from hating amarok at it’s core to loving it and seeing that no other media player can truly compete with it, I started a rather popular script for it, even got mentioned on linux.com, and several people have helped with it, their names are probably in the changelog at various points :).
Amarok is without question, the best audio player around, made even better with Googlyrics.