How do I remove a pedal from a crank with a crossed thread?
I'm guessing the pedal is toast too, but if I wanted to try to save it (and it refused to come out with simply a wrench and a hammer -- counter-clockwise on the right, clockwise on the left) I'd get out my trusty Dremel and make a slot or two in the crank, parallel to the pedal shaft.  (It won't hurt if you nick the pedal threads a little bit.)  Then drive a small cold chisel into the slots to spread them a bit.

(I do wonder how you managed to cross-thread the pedal and then ride on it.)