My favorite infringement story was a small family tun diesel and fuel oil company in Texas named Ewing oil company. They never thought twice about the name, which had existed for three generations, until the producers and lawyers of DALLAS (the tv show) contacted them when the show became the #1 rated show. From what I remember, they sold the trademarked name rights to the show for $5,000,000.
For those not old enough, the TV show was about an oil tycoon named J.R.Ewing who ran his oil empire named Ewing Oil Company.