Maiden at Donington - wanted to tick that off on my list for years, and it was a very special event. Great setlist, fantastic performance [as one expects from them].
Also went to see them a few weeks later at the O2 which was almost as good.
Soundgarden at Brixton Academy in September - fantastic show, interesting setlist. Had seen them at Download 2012 but this was much better. Made me want to be a performing artist of some kind because it looked a lot of fun.
Muse at the Emirates in May - one of the best live bands in the world right now with a range of brilliant songs and a phenomenal live show, very theatrical. Total progressive rock amazingness.
Rammstein at Donington - their live show is unreal, though I'm only a casual fan of their stuff.
Down at Donington - One of those bands who are decent on record but sound much more organic live and consequently are much more enjoyable in that environment. Not quite as amazing as they were in 2010 but still great.
St Vitus at the Garage in March - I've seen all three of the 'classic' 80s doom bands now - Candlemass, Trouble, St Vitus - and though the other two were good St Vitus were just incredible. Again, I like their studio stuff but live they are phenomenal and considering they've been around for 30 years plus they put most newer bands to shame. Very tight performance, the whole group were just on it. I've seen Sabbath six times with various line-ups so far and with the exception of the 2007 Brighton show that Vitus gig beat the lot of them.
Mothertrucker last night at The Miller were good as well, though I've only just started to get into them. I generally don't listen to much instrumental music but their material works for me as they keep the riff central to the songs a la Sabbath, and they also had some very Hawkwind style soloing as well.
[Edited by sabbathfan at 10:48 on 08/12/13]