I strapped on my super-heavy-duty hiking boots, put on my parka (EVERYONE had a parka in those days...), and left the house at about 1:00 AM. There were about six inches of clean snow on the lawns, but the roads were clear; it was about 10 degrees out (F; call it minus 12 C). There was a full or nearly full moon. Four and a half hours, and fifteen miles later, I came home.
I don't really remember what I thought about on that walk; I do know that I saw VERY few cars (four, I think...) and had a moon shadow for most of the walk; the forest preserves start about a mile and a half from my parent's house, and I was surrounded by woodlands and swamps for most of the trip. For one three-quarter mile stretch, North America's largest cemetery was off my left shoulder. Cemeteries make INTERESTING sounds in the middle of the night in the middle of winter...
It was pointless, exhausting, painful, and utterly magical, and I truly wish I had done similar things more often, and that I had more memories to compare with it.