I also made a password logger in high school (like presumably a great many bored kids). The network was all DOS machines where you used a command line tool to manually log in to a Novell server. There was no security in that system, so I wrote a simple wrapper that looked like the Novell login tool, saved the passwords and then shelled out to the real thing to provide access.

I didn't use the passwords for anything... But there was a guy in another class whose password was the name of the girl on whom I had a crush too. Illicit knowledge bred jealousy! Neither of us ever got the girl.