Good idea. There are so many variables that to really get a good idea of what's gets you going, it can help to know the times in different settings.

I do a lot of my writing at 750words.com, and I've learned a great deal about how I write, what times are good, and how fast I can really make things work for pulling it straight out of my head. One of the biggest things I've learned is that creating a writing habit makes it easier to get things out again - like this challenge reinforces writing every day before NaNoWriMo.