Audiobooks. I have a TON of time alone with my thoughts. If I didn't play audiobooks, I'd be listening to myself think probably 90% of the time I was awake. And my commuting route has almost NO sensible alternatives, so I ride exactly the same road every day, 250 or so days a year.

There's almost no cycling around here except for recreational, which is almost all on the weekend. And I almost never ride on the weekend, so I rarely see another cyclist. I can easily go a week or two in the summer, and all winter, without seeing another cyclist. Heck, if I leave early in the morning, I probably won't even see a car for the first 5 miles or so.