Those walk ons are so cool to witness,  I remember in 05 I took my son to see Buddy Guy open for Etta James and after the first song, John walked out the played the rest of the set with Buddy... It was so amazing to see.  i still remember Buddy saying oh the time is almost up and John walking over to the clock that was embedded in the footlights.  He took his jacket off and threw it over the clock, saying there was no time and they could play all night.  truly magical when you get those moments... 

have to see the greats, they aren't going to be with us forever and seeing them live is the best.
debbie