A similar question was asked at Yahoo Answers:
What is japan best known for? - Yahoo! Answers
Kome Kome Club's 1998 song "Funk Fujiyama" cleverly pokes fun at foreign stereotypes and caricatures about Japan including Samurai, Ninja, Geisha, Pagodas, Kamikaze Pilots, Mt. Fuji, the "Hino Maru" flag, Sailor Uniform students, Yakuza, Salary Men, Sumo Wrestlers etc.
YouTube - FUNK FUJIYAMA
The other stuff like Anime, manga and brand names like Sanrio-Hello Kitty are more along the lines of Japanese pop-culture stuff. Jpop and its artists like Utada, Koda Kumi, Hamasaki Ayumi, AKB48 etc. are starting to become more and more known especially in Asia.
The Shinkansen, Onsens, Sakura flowers, sushi and sake are also pretty identifiable with Japan.