Since I'd like to be good (or at least considered good) in my profession, I work on personal projects in my spare time to keep all my skills nice and sharp.
Now, I don't program stuff 24/7 mind you (I have to eat and sleep too). I like to draw, play video games, and exercise. But I always have an idea for something so I go about building it, thus taking up most of my time.
Since I sit on my ass enough through the day, I tend to go to the gym (I don't skip leg days); however lifting weights and looking like a clown doing so can only be fun for so long.