Being obsessive about food just got that little bit more interesting thanks to Fujitsu. Last year, the Japanese semiconductor company repurposed one of its factories to the production of lettuce, and this month its begun selling the special produce for around ¥500 ($4.90) per 90 grams. Thats a significant premium over conventionally grown greens, but then Fujitsus lettuce is being cultivated in the same sterile clean room environment as is demanded for silicon chip manufacturing. …