No, they are always different. Mostow Rigidity tells you that complete, finite-volume hyperbolic manifolds are determined by their fundamental groups. These groups never contain a $\mathbb Z \oplus \mathbb Z$, and any group acting on $\mathbb E^2$ contains this as a subgroup of finite index. Groups acting on the three-sphere are finite. This analogy generalizes to all $n$: Mostow Rigidity remains true (and these fundamental groups never contain $\mathbb Z^n$), Bieberbach Theorems say that the groups acting on $\mathbb E^n$ are virtually abelian, and the groups acting on the $n$-sphere are finite.
Matthew Stover
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