From the WSJ:Investors with plenty of cash on hand, thanks to years of low interest rates, have flocked to illiquid investments in search of outsize returns, often with the help of borrowed money. Some market experts worry that investing in illiquid assets, despite their inherent risks, has become almost mainstream.In 2006, U.S. institutions such as pension funds and endowments, had about $1 of every $10 invested in less easily traded assets -- such as hedge funds, real estate and private-equity funds -- up 27% from 2003, according to consulting...