If you have an hour long commute to work, one option may be to tape yourself talking, like an audio journal. I use the voice memo app on my iphone to record notes about my recent therapy sessions, thoughts that come to mind during the day, anything I want to write down and remember when I'm not at my computer.

I found that recording my thoughts as I'm speaking them is a great use of time while driving and leads to more insightful journaling.