Mod 2 Seiberg-Witten invariants of homology tori
  We show that the mod 2 Seiberg-Witten invariant can be determined for a spin manifold X which has the same homology groups as the 4-torus. The value depends on the structure of the cohomology ring of X, and in particular on the 4-fold cup product on H^1(X). We also consider some examples of homology tori. 
Daniel Ruberman, Saso Strle (Brandeis University)