It is NOT TRUE that writing exercises are the only kind I do. I have to walk all the way to the kitchen to get coffee, and I'm very conscientious about chewing my food thoroughly. But I do love writing exercises.
Whenever my #4 daughter (also a writer) and I are between projects or are stuck on projects, we get together and do exercises to loosen things up.
For instance, we did one where we wrote everything we could remember about one particularly vivid dream. She got a couple of stories and a novel out of that one.
Another time, we were talking about the fact that we used a lot of visuals and even auditory sensory impressions, but almost never used scent. So we did exercises all evening focusing on scent. No fair making the character unable to use any other senses--smell had to be the main impressions.
We had just had dinner at my most favorite restaurant in the world, the Shalimar Indian Restaurant on Hurstbourne in Louisville, Kentucky. I ended up writing a flash (very, very short) fiction love story with the Shalimar as one of the characters. I edited it, polished it, typed it, framed it, and took it to the manager of the restaurant. It's now hanging on the wall in their waiting area. That's one of my best publishing credits.
To read more about writing exercises and... well, more about all aspects of writing, please consider attending the FREE online Virtual Writers' Conference May 19-22, 2009.