Specific concerts that I was not at:

• Various Slane Castle concerts:
  • 16 August 1981 Thin Lizzy (with U2 and others)
  • 5 July 1986 Queen
  • 11 July 1987 David Bowie
  • 23 August 2003 Red Hot Chili Peppers (with Foo Fighters, Queens of the Stone Age and Feeder)
• Oxegen Festival 2004 with:
  • The Cure
  • Muse
  • Bell X1
  • The Strokes
  • Kings of Leon
  • Scissor Sisters
  • Electric Six
  • Pink
  • Ash
  • Hal
  • The Killers
  • The Libertines
  • The Shins
  • Elbow
  • Snow Patrol
  • Belle & Sebastian
  • Bic Runga
• Journey at the National Stadium, Dublin 25 July 2008
• Elton John at Thormond Park, Limerick 6 June 2009
• The Bealtes' rooftop concert 30 January 1969
• The Beatles (any other concert)
• The Doors (can't find anything specific, but they are too amazing to leave out and I will never see them)
• Radiohead, Malahide Castle, 7 June 2008
• Blink-182, San Francisco CA, 13 September 2009 (with Weezer and Taking Back Sunday)
• Panic! at the disco (with the Dresden Dolls and the Hush Sound) New York Nokia Theatre 28 June 2006

I can't think of any other specific concerts, and I am too tired to look for them. I know I am missing some performers though - Owen Pallet, Reuben, Sigur Rós, The White Stripes/The Raconteurs, Patrick Wolf and I didn't include concerts of people I saw - or have tickets to see (with the exception of some Oxegen bands and Blink-182 [but Weezer needed a mention])