On U2's Vertigo tour, Bono has brought attention to a symbol for peace and harmony, which adorns the singer's headband during an intense part of the show. But the symbol has also prompted a trademark

On U2's Vertigo tour, Bono has brought attention to a symbol for peace and harmony, which adorns the singer's headband during an intense part of the show. But the symbol has also prompted a trademark infringement battle. Read Susan Butler's column.