Cutting corrugated iron seems either dangerously hard work with snips, or involves some fancy powered cutting tool. In fact for simple cuts one can just tear the metal by hand.
For the great chicken coup project we realised that I have a pile of old corrugated iron from the garage reroofing. Of course it was in 6m lengths, and I wanted 50cm strips. Looking around on the net I found a curious reference to tearing the metal by hand. Having very little to lose we tried this. First cut a notch at the point you want to tear. Then smoothly, as if tearing material, rip the metal upward. The edge is remarkably straight (perhaps a result of built in grain structure from the rolling process) and has no heat damage or scratching on the galvanised surfaces. Watch Tobin rip cold metal with his bare hands (actually, welding gloves).