The 20 century may well go into history books of technology as the century of the silicon chip. Silicon and its siblings, the III-V semiconductors, are unquestionably dominating electronics and photonics as we know them. These are just a handful of elements from the periodic table. Why these? What makes them so successful? Are there things they cannot do? Could we overcome such limitations by reaching out to other elements? Which ones and why? Nobody has good answers to these technologically and economically extraordinary important questions. But we can speculate.