In this work, we have explored the potential of regularized second-order perturbation theories for predicting the correlation energies of extended systems, using κ-MP2 and the newly proposed xBW2 as representative examples. While neither of these methods is a silver bullet that cures all deficiencies of canonical MP2, regularization consistently leads to an improvement. In particular, κ-MP2 appears well suited to describe screening effects in metallic and polarizable systems. Meanwhile, the xBW2 method provides a remarkably effective remedy for the breakdown of MP2 in the strongly correlated limit of the one-dimensional Hubbard model.