Cat—vital. If Moe isn’t sitting on my papers as I write, I feel incomplete. Given that Dr. Moe-bius is 17 years old now, and there are no other cats in the household, this incompleteness without a cat could be a problem in the future.
Pen and paper—equally vital. I can write without a computer, and usually do, but the words have to go somewhere and get there somehow.
Music—not quite as vital, in that I don’t always listen to anything as I write. But it’s always an inspiration. In fact, just thinking about Calibro 35‘s last collection of tunes from 2011 has been a big help in finding a mood for my latest short story (the floundery-dolphiny one).
What’s on your list?