Benny and Björn joined U2 on stage during their Zoo TV Tour and joined in with Dancing Queen. The crowd went wild as lead singer Bono introduced them.

At the end Bono told them, "We're not worthy".  Indeed.

Release information:
This performance has not been included on any officially released video or DVD although very small clips of the Benny and Björn appearance have appeared on The Winner Takes It All - The ABBA Story and Super Troupers - 30 Years of ABBA.

Benny almost head-butted his keyboard in acknowledgement to the crowds' cheers!

Thanks to Paul Russell, Pascale Ranson and Robert Verbeek (RIP) c/o ABBAMAIL (no longer online). Extra thanks to Jozsef and Philippe Dupont.
YouTube link c/o SuperSpurs 69