1) King Crimson, Town Hall, New York City, Discipline Tour 1981. Absolutely remakable!
1) King Crimson, Warner Theater, Washington, DC, Thrak Tour w/California Guitar Trio as opening act. (199?) The double Trio line-up was just amazing to listen to. Jaw-dropping, awe inspiring -- Fripp continues to be God.
2) Talking Heads, Radio City Music Hall, 1980, with expanded line-up including Nona Hendrix, Adrian Belew, Busta Jones, et. al. The day before the Central Park concert that showed up on record. A brilliant show from start to finish.
3) Jorma and Jack -- acoustic Hot Tuna. can't pick a date and place. Always incredible together, now and then.
3) Richard Thompson and Danny Thompson (the "Thompson Twins'!!) 1994, Wolf Trap. Another acoustic duo that can do it all. Virtuoso playing and wonderful songs.
4) Elvis Costello and the Attractions, don't remember the year, but I saw them at Radio City Music Hall, the year they did the tour with the Roullette wheel that determined what songs they would play. They were an incredibly tight band that took the songs and turned them inside out playing them in completely different arrangments and styles. It was a great concert.
5) Fairport Convention, 20th Aniversary reunion festival, Cropredy, Oxfordshire. It was great even before Fairport appeared, and Fairport with all the personnel assembled in the various line-ups just blew everybody away. I still remember being totally mesmerized by the rendition of a "Sailor's Tale" (the live recording of the song show just doesn't convey the same thing). Robert Plant's appearance to sing a few songs with the lads was a great added bonus.
6) Ok one more. Blondie and Rockpile at Belmont Raceway in New York. (1980?). Just because it was just a wonderful day of fun and great music. Rockpile (Nick Lowe and Dave Edmunds w/ Billy Bremner and Terry Williams) were as tight, as spirited and having as much fun as was possible. Blondie, too were at the top of their game.
To be honest there are many other concerts to choose from. Many less event-like but just great evenings of music. Like the first time I heard June Tabor sing in a London folk club, or hear John Renbourn play guitar, or Bert Jansch perform, hearing Oregon and Ralph Towner play, Jan Garbarek and Hillard Ensemble performing Officium at the Catholic Cathedral in Washington, D.C. in '94 or '95. or about 6 or 7 (?) years ago when Paul Kantner pulled some people together to tour as "Wooden Ships" and do some great acoustic versions of Airplane and other songs, or Pete Townshend at the Brixton in London in 1986 (Pete Towshend's Deep End Live!), actually, most recently Bjork was absolutely incredible at the Royal Opera House in London a couple weeks ago, and the list really goes on.... (do we really have to stop at 5?)