[Photos via PMc] Musician Sir Ivan L. Wilzig's Watermill home is a 12,000-square-foot castle known as the Playboy Mansion of the East Coast and the perfect location for huge extravagant summer parties which Sir Ivan is certainly known for throwing. He is gearing up for his highly anticipated Hamptons bash this Saturday with this summer's theme, "Castlestock 2009" in honor of Woodstock's 40th anniversary to benefit the Peaceman Foudation. Flowered attire required, of course... You might know Sir Ivan as "Mr. Mitzvah" from the reality TV show "Who Wants to be a Superhero?" or Mr. Lily Pond, as we like to call him as he's been a permanent fixture at the East Hampton hot spot all summer. More photos below of his sprawling, exotic estate during his 2007 Superhero-themed party...

Sir Ivan's 2007 "Who Wants to be a Superhero" Party