AP Wikipedia co-founder Jimmy Wales stands in the doorway to his office Friday, Dec. 1, 2006 in St. Petersburg, Fla. Wikipedia is one of the largest reference websites in the world, attracting some 1.7 billion visitors a month. When it launched in 2001, the free, collaborative concept was a far cry from the traditional, bookshelf-hogging encyclopedias of the day. Coming up on Tech Tuesday, the co-founder of Wikipedia talks about his 20-year-old innovation and what he’s working on next. Guests: Jimmy Wales, co-founder, Wikipedia Related Links: