I read this on his blog and i want to try it :
I like people watching. It's fun. You go, you sit on a patio or something with a friend, and you watch people go by. The two of you can make up little stories in your head for them. I mean, I think we make up little stories for people in our heads anyway, on an unconscious level. Stereotyping is a part of that. But when you're people watching you think about it more.
But what's even more fun, especially if you live near a college or university, is to get up high, at night. Not too high, but above head-level. In a tree, or on a ledge in shadows. And then you and your friend just sit quietly, and you sit still, and you wait for groups of people going to and from parties, or to and from friends' houses, and you listen. You get a snatch of conversation, here or there. It's like people watching, except you can get a bit closer to them. It's almost like for a brief second you can hear their thoughts. People listening!
Another hobby that's just one step closer to stalking!