Any question answered...

Got any lengths of scaffolding pole lying around? Very handy stuff. If the pedal's off the crank you can slip the scaff pole over the crank to use as a cheater bar and give you more leverage.

Unfortunately not. Though there is a scaffold outside my window right now that I could try stealing bits off in the dead of the night once the builders have fucked off, though I can't get the opposite pedal off either - I've just destroyed a pedal spanner trying, in fact. It's all warped and mangled and the bolt on the pedal hasn't moved a nanometer :-)