Mega Millions mania… one of the largest jackpots in history - now estimated at a staggering half a billion dollars - is up for grabs on Friday night.  But does winning all of that money really buy happiness?  Right before the live lotto drawing at 11 pm on Friday, "20/20? looks at past lottery winners and losers, as well as the scammers and swindlers who vie for a slice of the winner's pie.  Why do so many lottery winners end up broke?  What about the office pool?  Can you play the odds to win?  Anchored by Barbara Walters with reports from Dan Harris, Jay Schadler, John Berman, Nick Watt and Cecilia Vega, "Lotto Frenzy: Be Careful What You Wish For" airs on "20/20? on FRIDAY, MARCH 30 (10:00 - 11:00 p.m. ET) on the ABC Television Network.

           David Sloan is executive producer of "20/20?.  

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