  This paper aims to study the use of future SNAP data together with the result
of searches for strong gravitational lenses in future large quasar surveys to
constrain the Generalized Chaplygin Gas (GCG) model. The GCG is considered as a
possible unification scheme for dark matter-dark energy. It is found that both
experiments should be able to place important constraints on the model,
especially when both tests are used together.
