It depends on your mood. These things differ from a person to another.
I, for example, take special interest in the following things:
Reading history, psychology and fiction.
I love watching cult movies and documentaries about outer space.
I own a telescope and every now and then when the sky is clear,
I go out with my music player and I have a good time stargazing.
I go out and jog regularly - you'll never guess how great it makes
me feel.
What else? A lot of stuff. You have to let us know what kinda
personality you got there