  Consider a smooth affine algebraic variety $X$ over an algebraically closed
field, and let a finite group $G$ act on it. We assume that the characteristic
of the field is greater than the dimension of $X$ and the order of $G$. An
explicit formula for multiplication on the Hochschild cohomology of a crossed
product of $k[G]$ and $k[X]$ is given in terms of multivector fields on $X$ and
$g$-invariant subvarieties of $X$ for $g\in G$.
