I just found out about this happening at U2′s concert in Berlin a week ago (18th July).

Three young guys from the Czech Republic were at the concert, holding up signs with “Me + Guitar = Angel of Harlem”, “Me + Drums = Angel of Harlem” and “Me + Bass = Angel of Harlem”.

They’re no ordinary fans – they play in a U2 tribute band in Prague and they were trying to get the band’s attention – they dreamed of playing on stage with them and having Bono on vocals. Sure enough Bono noticed them and invited them up on stage to play Angel of Harlem. The other members of U2 chatting with their stand-ins and dancing to their music.