Here's a tip that sound's strange because writing is generally a solitary endeavor, but it helps me when I write:
No, this isn't about having a sunny disposition. It's about productivity. Not only does smiling make me feel better as I weave my words, it also seems as though the words come more easily. Perhaps it's because we associate smiles with confidence or contentment (both of which writers seem to have in short supply) and so our brains tend to follow suit when we change our faces.
Smiling is also about attracting readers: It's the writing equivalent of the fact that the phone company (way back when there was one phone company) trained its operators to smile when they spoke with customers because you really can hear the difference. We talk (often obsess) about Voice. Just like a spoken voice, I think a smile comes through as part of your written voice, particularly in terms of the enthusiasm with which you tell the story.
I won't promise that you'll write faster, but I think smiling will make both the process and the product better.
I have a longer discussion of this notion on my blog as part of a series of posts on how Dale Carnegie's principles apply to modern writers.
What an unusual but awesome tip, Deren. I'm so glad you shared it! I know I often emote my writing, especially if the scene is particularly funny or sad, but I'm not sure if that's normal. I hope so!