What is the secret tool of success?

For his book The Millionaire Next Door professor Thomas Stanley interviewed two thousand millionaires, and the main tool of it their success turns out to be: the Rolodex. That's the slightly dated revolving card system with names, addresses and telephone numbers. Everybody has a digital version of it in his smartphone. It is an address file, but more than that. It is organized, structured and detailed. It provides information in the areas of region, sector, interest, age, profession and whatever you want or find useful. The key to the success, according to Stanley’s research, is; working exclusively with high quality contacts. That is, people who can and will assist you with advice, ideas or sometimes even actual help.