"The following is not a futuristic scenario. It is not science fiction. It is a demonstration of...an extremely* unlikely, yet intellectually fascinating query: What would happen if the earth stopped spinning?" SPOILER: Our continents become one.
If that spoiler wasn't enough, the slightly longer explanation is that, without centrifugal force, the ocean water near the equator would migrate to where the Earth's gravity is the strongest, the poles, leaving us with dry land in the middle.
If that's still not enough, good for you, science geek. The even longer (best) explanation can be found here: [esri via nerdcore via neatorama]
* You know, it did happen before, in the Superman movie (1978). And if that's not foreboding enough, I don't know what is. Also of note, Superman only saves Lois when he goes back in time. That's fine if there's another Superman hanging still around from the past, fixing dams and stuff while the alternate Superman gets the girl. But what happens, like, when the deed is done. Are there perpetually two Supermen hanging around, getting up in Lois' grill? Does one Superman have to be Clark Kent all the time? Do they flip a coin to choose identities or alternate days? I don't think** so. I think that, when Superman went back in time, the two bodies united as one. And you know what that means? Everyone who wasn't the esteemed Lois Lane died. Nice job, Superman. Nice job.
** I haven't seen that movie in almost a decade. It's possible that my facts are screwy and I'm ranting about nothing.