"Here's the deal," Bono said before U2 launched into an impromptu performance of the Joshua Tree classic "One Tree Hill" last night in Chicago. "If we screw it up really badly, you don't put it on the Internet." Lucky for the internet, the band did just fine with the song, which was dedicated to the memory of the singer's former assistant Greg Carroll, who died 25 years ago this week. "One Tree Hill" is typically only played during the band's concerts in Australia and Carroll's native New Zealand. The tune capped off a long gig that mainly emphasized songs from the band's Nineties output, including five numbers from Achtung Baby, two from Zooropa and the soundtrack hit "Hold Me, Thrill Me, Kiss Me, Kill Me."