I very rarely get alone time. When I do its usually not that long, so I tend to do quick easy things like catch up on TV shows or do some reading.
On the rare opportunity that I get a few hours to myself, I like to grab my camera and go out to take pictures. I can spend hours just roaming a park shooting flowers or landscapes, photographing old architecture or anything that catches my eye.
A mani/pedi would be nice too!