Having an amp crap out on me on a NYE gig was the most fun thing ever! These days I think my bandmates think I'm a bit odd for having spares of everything, but having had two amp failures at gigs I'm not taking any chances. I worry for them if they have a failure though. Drummist always has spare sticks and skins, but our guitarist has a Boss Katana combo with a footswitch that's a bit temperamental and no means to DI from her pedalboard, and our keyboardist's keyboard isn't treated very well, so if either of them have an issue we're screwed. We were nearly in that situation last summer when the keyboard had a bit of a moment, leading to a hasty rearrangement of the set, but no lessons appear to have been learned.