Most memorable:
Santana, Black Sabbath and Van Halen at Nassau in the early 80’s (separately)
Clapton (from a box overlooking the stage) at the Albert Hall in London early 90’s
Rock&roll HOF 25th anniversary show at MSG- Google it - Springsteen, Billy Joel, BB King, Stevie Wonder, CSN, Jackson Browne, James Taylor, Simon and Garfunkel, Sting, Bonnie Raitt and a few others. Playing together and separately for hours. The 2nd night was a whole different lineup.
allmans at MSG just before COVID hit.