I was gonna say your favourite but then I realised there's no way I could narrow it down to just one so the ones ive chosen would all be on par for whatever reason. Obviously I like very different types of music and so Ive enjoyed each of these for different reasons wether that be pure enjoyment or sheer amazement.
Heres mine anyway in no particular order:
Rage Against The Machine - Leeds Festival 2008
Arcade Fire - Leeds Festival 2007
Justice - Leeds Festival 2008
Camera Obscura - T In The Park 2009
Manic Street Preachers - Leeds Festival 2008
Human League - Evolution Festival, Newcastle 2009
Bloody Beetroots - Death Disco @ Arches, Glasgow 2009
Boys Noize - T In The Park 2009
Etienne De Crecy - Beats N Cubes Tour, Leeds 02 Academy 2010
2 Many DJs - Newcastle 02 Academy 2009
Blur - T In The Park 2009
Kings Of Leon - Newcastle Arena 2007
Hmm seems most of my favourites have been in the past 3 years. Also I couldnt keep it to just 10. sorry.
While the rest of the bands and DJs i still love, Kings Of Leon really pissed me off at Leeds last year. The gig they did in 2007 (also at Leeds as well as Newcastle) was fantastic. It was around the time they released the third album. Then last year at Leeds they played all their "shitkicking" songs from their first two albums in a slower, more relaxed tempo so they would fit in with their new radio friendly arena rock shite from their more recent albums. It was the fourth time id seen them and the first time they played Red Morning Light but they slowed it right down and did the same with Four Kicks, The Bucket, Pistol Of Fire, Mollys Chambers and California Waiting. As a result some of them just sounded awful because thats not the way the songs where intended. The two times I saw them in 2007 was fantastic, but the latter two times (both after the fourth album was released) where awful, especially their set for Leeds. A damn joke.