BlueCross BlueShield of Illinois / BCBSIL  http://www.bcbsil.com/index.html

"Blue Cross and Blue Shield of Illinois traces its roots to the depths of the Great Depression and a group of Chicago business leaders who witnessed how relatively minor illnesses that required a hospital stay were ruining families financially.  In 1936, they pooled their own savings and launched a not-for-profit company called Hospital Service Corporation to offer an affordable pre-paid hospital plan, which was a new concept at that time.  The Chicago Plan, as it was called, was one of the forerunners of what we know as health insurance today."