Gelfand-Fuchs cohomology of invariant formal vector fields
  Let $\Gamma$ be a finite group acting linearly on a vector space $V$. We compute the Lie algebra cohomology of the Lie algebra of $\Gamma$-invariant formal vector fields on $V$. We use this computation to define characteristic classes for foliations on orbifolds. 
Ilya Shapiro and Xiang Tang