Best concert you've attended

Richard Thompson

John Cale

Jim Carroll

NRBQ

Ramones

Allman Brothers

George Jones

A toss-up:

Santana at Merriweather Post Pavillion in the early Eighties or Yes reunion at DAR Constitution Hall, D.C. (the acoustics were sublime).

Lynyrd Skynyrd a mo or so before the crash in Pittsburgh PA with Charley Daniels

Elton John

Steely Dan 4x

Billy Joel when he was young 1970-1980

Captain Beefheart and the Magic Band with It's a Beautiful Day at the Fox West Coast in Long Beach circa 1972.  Close second place: Blodwyn Pig at The Splinter Brothers and Sisters Warehouse, Phoenix, same era. Jethro Tull at the Phoenix College Gym  (circa 1969) and The Mothers of Invention (Phoenix Star Theater, right after "Freak Out" was released) are reasonable contenders, too.

Led Zeppelin Kezar Stadium 1973

Lynyrd Skynyrd, Marshall Tucker, Allman Brothers Band Winterland 1973

Countless Grateful Dead shows