Are there non-trivial examples of sentences where the use of one case, instead of other, changes the meaning?

Question

Are there examples of German sentences where the use of one case instead of other alters the meaning, but still being the sentence grammatically correct? *Edit*: I'm after sentences in which *only* the case changes (but otherwise the sentence should be the same).

Answer 1

Der Mann sieht es. – The man sees it.

Den Mann sieht es. – It sees the man.