Today's question was : Brennan Avenue on the south side is named for an obscure man who made an amazing contribution to Chicago. Who is he, and what did he do?

Scott Batzel knew Brennan Ave. was named for Edward Brennan, who invented Chicago's street grid numbering system. A building inspector from the near West Side, Brennan's idea started as a letter to the editor. The street numbering system designates State and Madison as "O" and has street numbers going east, west, south and north from there, making Chicago possibly the world's easiest city to navigate. He also renamed many city streets. The system got started 100 years ago, in September of 1909.

If Scott can send me his address and shirt size, I can send him his prize.