Like @Bilbo I had the first Def Leppard single on Bludgeon Riffola, although I am sure it was 'Get your rocks off' with 'Riding into the Sun' as B side. I also saw Iron Maiden fronted by Paul DiAnno at the Marquee (supported by the awful Praying Mantis) and had a demo single of 'Prowler'. With my NWOBHM quality threshold on low, I also had Fist's 'Name Rank and Serial Number' single. Moving swiftly on ...
Other memorable moments: like @Frank Blank I saw SPK, although this time supporting Throbbing Gristle at Heaven in Charing Cross - at one point TG's video showed a scrotum (animal I recall, like a goat) being slit and a testicle dropping out. Nice; buying Noel Gallagher a pint at the bar at the Toxic Twin Towers gig c.20 years ago and failing to offer my bass services, despite the recent departure from Oasis of Guigsy; having a quick chat with Greg Lake after a charidee do c15 years ago where he played 'Lucky Man' and discovering that he didn't sound ANYTHING like a choirboy when speaking; standing behind Nick Cave in the queue at a parent teacher conference (our eldest sons each went to same school in London) and also failing to say anything at all