The Guardian has a great feature publishing pictures of the rooms where some famous authors write, including commentary by the writers. Very fun to peruse.
Now that our detached garage has been converted into an art and writing studio for Annie, she'll be moving out there, and I'll be reconfiguring my own space in the house. I like to have a room with all my books and papers. But the place I end up writing the most is in the living room, feet up, laptop (that has no internet capability) on my lap.
Answers to above:
#1: Nobel laureate poet Seamus Heaney
#2: Novelist fantastique Sarah Waters
#3: Writer of one of my favorite novels ever (The Master), Colm Toibin