I repaired a friend's Peavy Delta Blues (it's basically a Classic 30), and when it didn't work at first, I opened it up in frustration and started poking around haphazardly around the power supply area. The electric shock woke me up a bit though.
The repair was fine, it was a broken fuse.
I do not find electric shocks entirely unpleasant...
Guit Boxes: 87 MIJ Strat, Ibanez MIJ RG540, Korean Fender Dreadnaught, The Loar LH-500 (1934 L-5 Reproduction)
Amp: Marshall TSL100 amp head with JCM900 1960 Lead 4 X 12 angled cab
Effects: Crybaby, TS10 Tube Screamer, Badder Bad Monkey, Boss Metal Zone