I've always thought it totally bizarre that the US, with its supposed reverence for the constitution (you know, the one that guarantees the sacred 'right to bear arms' that accounts for 30,000 people a year?), which explicitly bars 'cruel and unusual' punishment, should allow things like lethals injections, gas chambers and - worst of all - the electric chair. What in God's name could be more cruel? And how 'usual' is it to wire sentient beings up to the mains? If you want to execute people instantly and painlessly, there's no mystery about it. Do what the Chinese and Russians used to do (and may still, for all I know) - shoot them once in the back of the head. Done.