Expo 70

Expo 70, officially the Japan World Exposition, Osaka, 1970, was a World Expo held in Osaka, Japan.

Red five-pin dora riichi mahjong tiles

It has been said that the red five-pin dora riichi mahjong tile was invented for Expo, although that might not actually be the case.

Time capsules

Osaka-based company Panasonic, who famously made a $99 Blu-ray, created two time capsules, one of which was opened 30 years after Expo had ended and will subsequently be opened every 100 years, while the other will be opened in 5,000 years, meaning the year 6970.