I used to try and take pictures of the television and of video games so that I could get better at it.
It sounds a little stupid, but it's generally difficult to take good pictures of a television set given the way scan lines work. This was particularly difficult before digital photography because I was working with a limited number of shots and of course had to pay for each frame.
The reason this was necessary was for taking pictures of video game accomplishments; I was a big fan of sending things off to Nintento Power Magazine.