I believe there are people that are working on doing just that.I've read somewhere that the Insight's motor has armatures that are modular, meaning you could disassemble the trans and stack motors (similar two the way Mazda's rotory engines can be 2 or 3 rotor and you could do 4 or 5 if you had some machining tools). Is this correct?
That could make for a powerful all electric project.
I also saw this the other day:
http://www.plasmaboyracing.com/blog/?p=337
Crazy stuff!