Yes, that’s four billion Microsoft Points right there. An error in the Xbox Live Rewards program awarded many users more Microsoft Points than they were supposed to receive. To most people this amounted to less than $5 worth but this user reported a gain of $53,687,089.20. Imagine all the content you could buy with that. In the end it was all for naught as Microsoft quickly reclaimed all the points awarded in error.
UPDATE: Apparently what caused this was Microsoft gave the user too many points, which he proceeded to spend right away, so when Microsoft went to take the points back, his Points went into the negative, causing the glitch to occur.