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Ian Agol
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Let $M$ be a 3-manifold fibering over $S^1$, so there exists a fibration $\Sigma \to M \to S^1$. Then $M\times M$ will admit a symplectic structure.

There is a symplectic structure on $M\times S^1$, associated to the fibration $\Sigma \to M\times S^1 \to S^1\times S^1=T^2$ which is trivial in the second factor, by a result of Thurston (the converse also holds).

Similarly, there is a fibration $\Sigma \to M\times M \to S^1\times M$ which is trivial in the second factor. Hence by the result in the fourth paragraph of Thurston's paper, $M\times M$ admits a symplectic structure.

I think these manifolds cannot be Kähler usually. See the main result of Biswas-Mj-Seshadri.

Ian Agol
  • 68.9k
  • 3
  • 194
  • 358