Carl Icahn, Chairman of Icahn Enterprises, is worth an estimated $20 billion and has made his fortune by being a shareholder activist (what they used to call a corporate raider).  He recently announced a large stake in Talisman Energy which has been an underperformer for years.  He now has two board members and has expedited asset sales.

The stock hasn't performed yet...

"You should always do better than the market, and you shouldn't lose."