  Cosymplectic and normal almost contact structures are analogues of symplectic
and complex structures that can be defined on 3-manifolds. Their existence
imposes strong topological constraints. Generalized geometry offers a natural
common generalization of these two structures: $B_3$-generalized complex
structures. We prove that any closed orientable 3-manifold admits such a
structure, which can be chosen to be stable, that is, generically cosymplectic
up to generalized diffeomorphism.
