Well, there's some ways in which this could be done - at least, the concept. Really it would be more feasible for a deep space type area, where you basically have no gravity but you can have areas that do. They include basically blocks that sort of glue you to their surface, or that basically force 1g upon themselves and 1 or 2 blocks next to them - presumably you'd need different variants to make different 'down' directions so that you could actually have a supposedly artifical gravity situation. Big spinning wheels are the traditional example, but would probably be a mess in minecraft.
Your own suggestion could work, but you could basically use the same idea - ground tiles that force 1g upon themselves and a bunch of tiles directly above them, so that you can just run outside and you're in low g again. You could always cover them up if you don't want to see the tiles, but you can control the whole thing pretty well.
My 2 cents.
