Also (even though it was already said that this is a parody), the first alphas of starcraft1 were based on the warcraft 2 engine. Screenshots are available:

http://www.sirlin.net/storage/post-images/starcraft_alpha.pn...

( I think they abused ships for the flying units somehow, even though I am unsure about the precise details).

I think this is a cool detail to know, and it makes me curious if the first alphas for starcraft 2 were maps and hacks of starcraft 1 or warcraft 3 :)