Non-perturbative plaquette in 3d pure SU(3)
  We present a determination of the elementary plaquette and, after the subsequent ultraviolet subtractions, of the finite part of the gluon condensate, in lattice regularization in three-dimensional pure SU(3) gauge theory. Through a change of regularization scheme to MSbar and a matching back to full four-dimensional QCD, this result determines the first non-perturbative contribution in the weak-coupling expansion of hot QCD pressure. 
A. Hietanen, K. Kajantie, M. Laine, K. Rummukainen and Y. Schroder