In other buyout news, insurance broker Aon ( AON) and human resources company Hewitt Associates ( HEW) said Monday that they have agreed to have Hewitt merge with a subsidiary of Aon under a deal that values Hewitt at $50 a Hewitt share. This represents a 41% premium to Hewitt's closing stock price on July 9, the last trading day before the agreement was announced. The estimated total value of the 50% cash and 50% stock transaction is about $4.9 billion. Aon stock has fallen 8.2% to $35.21, while Hewitt has skyrocketed 31.9% to $46.68. Also on Monday: Playboy Enterprises' ( PLA) Hugh Hefner has offered to acquire all outstanding shares of Class A and Class B common stock not currently owned by him for $5.50 a share in cash or about $185 million. This represents a 39.6% premium to Playboy's closing price of $3.94 on Friday. Playboy stock has jumped 33.3% to $5.25 in two hours into Monday's trading session. -- Reported by Andrea Tse in New York Get more stock ideas and investing advice on our sister site, Stockpickr.com. Follow Andrea Tse on Twitter and become a fan on Facebook.