For me a favourite concert is like a favourite piece of music - I have several different 'types' of favourite.
I saw Pink Floyd - still with Roger Waters - perform The Wall at Earls Court in London twice ('80 and '81). Those shows stand out in my mind as the most profound concert experience I've ever had.
Probably the most exciting and fun concert I can remember is John Cougar Mellancamp at Hilton Coliseum in Ames, Iowa in 1988. It was just one of those nights when I was with a great group of friends, the band was brilliant and it was just great entertainment from start to finish. 10cc at the De Montfort Hall in Leicester in '76 runs it pretty close.
Alternatively there was Genesis at Knebworth in the summer of '78. Not so much for the quality of any of the bands but more because it was the first open air festival I had been to (which was something I'd wanted to do for a while but couldn't afford it). Like they say, you never forget the first time.
Finally there's the "what the Hell was I thinking" favourite. I'd been seeing in the New Year of 1982 with a friend who lived in London. We both got massively drunk and slept well into the afternoon. When we finally surfaced we decided we'd go see a band that night. We were in London - there's always plenty of gigs to choose from, we're bound to be able to find something laid back and mellow to soothe our hangovers we thought. The only band that we could get tickets for -
Black Sabbath ! Trust me, this is not the best way to cure a major hangover
Confused ? You will be...