  We find the gravity dual of a marginal deformation of ${\cal N}=4$ super Yang
Mills, and discuss some of its properties. This deformation is intimately
connected with an $SL(2,R)$ symmetry of the gravity theory. The $SL(2,R)$
transformation enables us to find the solutions in a simple way. These field
theory deformations, sometimes called $\beta$ deformations, can be viewed as
arising from a star product. Our method works for any theory that has a gravity
dual with a $U(1)\times U(1)$ global symmetry which is realized geometrically.
These include the field theories that live on D3 branes at the conifold or
other toric singularities, as well as their cascading versions.
