In an effort to help folks know what your personal experiences are and make it search able, I thought we could start off by listing the gear you have now and what you have used in the past. Feel free to embellish with stories ;-)
I'm relatively knew to headphone listening getting rather serious in the last couple of years. I don't have a separate head phone rig for the house yet, but am considering one. All my experience is in the portable field.
For Players I started with and moved too:
iRiver H10 20gb (brick) > Sansa E230 > Sansa Clip (still used for Audio Books) > Cowon J3
Sony Ear buds > Bose IE2 > Phonak Audeo PFE 112 > Westone 4r's
For Head phones:
Koss Porta Pro > Audio Technica M-50's > Audio Techinica ANC7b's Noise cancelers.
Motorola SD10 - HD
Used for mowing the lawn, yard work, and building projects. Not the best for sound but make it convenient for answering the phone and not having the player in my pocket or being encumbered by wires.
The Porta Pros still get used in the garage. The M-50's get used in the house on one of the rigs, and the 7b's get carried with me for flying and listening to audio books. The 7b's haven't got any music duty yet because the I prefer the sound form IEM's.
I don't have any experience with head phone Amps or DACs. All of the impedance ratings of my phones don't really require them. All of my music is ripped to FLAC. A time consuming process, but well worth the time.
I'm so happy with the Westone 4r's that I'm considering getting some custom IEM's from JHAudio.
So what's your gear?