I've not been to that many "big gigs" because to be honest, I'm not a massive fan! Perhaps I'm just lazy or something, but I've never found it a particularly wonderful experience being on your feet for hours, needing the loo and/or a drink but not being willing to fight your way through the crowd, the tallest man in the world standing in front of you, the loudest, most obnoxious man in the world standing behind you, having music played at volumes which are certain to damage your hearing and actually reduce your ability to hear the nuances anyway... being charged £15 for T-shirt which will fall apart after a week...
I know - I'm a miserable old git
That said, I have loved some of the mini-festivals that go on, like GoJonnyGoGoGoGo in Leeds, with small bands you just wouldn't hear or think to go and see otherwise, and lots of little quirks - quizzes, sweets, raffles - all that twee indie stuff, and imaginative merchandise (I still use my "Zombina and the Skeletones" guitar pick all the time!).
The bigger gigs I've been to have been my absolute favourite bands, for whom it gives me a thrill just to actually be there, so, I've seen Belle & Sebastian twice and Iron & Wine twice. The first time I saw Belle & Sebastian, I'd only been into them for a couple of months but I was totally in love with their music and a series of coincidences and last minute changes meant that I only discovered I could go on the same morning as the gig, after days of being miserable because I thought I was going to miss it. I was in a dream like state, it was brilliant.
Perhaps that's what other people get at all these other gigs... I've got a friend who's always excitedly telling me who he's been to see recently. I'm not much of an idoliser I suppose, so unless the experience itself is fantastic without the "OMG I CANT B-LEEV IM WATCHIN TH KILLERS!!!" factor, I can take it or leave it.
Oh, Eels. I saw Eels (with strings) on the Blinking Lights tour at the Manchester Apollo. Seated, with a Russian animation for support. That was pretty darn good.