I don't need quiet. I've worked with hammering, pounding, and jack hammers going. I've had cats crying, birds chirping, and dogs barking. Kids screaming outside. Snow plows going up and down the street.
I don't need a comfortable chair. I've worked perched on the edge of my DH's chair, which is too big for me and my feet don't touch the floor. I've resorted to the floor, the couch, and the armchair surrounded by bookcases, insulation bales, exercise equipment, and boxes.
I don't need a big monitor, good keyboard, or mouse. I'm using my laptop without the 19" monitor, keyboard, or mouse. They're all packed away. I'm managing.
I don't need music. My Bose has been packed away for a while and my Rio is in my exercise bag, permanently tuned to Books on Tape (only they're not called BOT any more).
What I need ...
My h/h firmly in my head. The scene in front of my interior screen. A clear idea of the plot. If I deviate from that, I stumble and mumble. So my writing notebooks -- those little 5x7 cheapie notebooks I carry with me wherever I go -- those are gold to me. Those and the memory stick holding the most recent version. They all go with me now as I gravitate from room to room, office to home office, hotel room (displaced for one night) and travel.
As long as I have them in front of me, I can write just about anyplace. It's a comforting thing to know .... but I have to tell you, I miss my 19" monitor, my Bose stereo, my keyboard, my ....