  Lately, much interest has been directed towards designing setups that achieve
decisive tests of local realism. Here we present Bell tests with measurements
based on linear optical displacements and single-photon detection. The scheme
displays good tolerance to loss. In particular, for entangled squeezed states,
we find thresholds compatible with current efficiencies of detectors and
sources. Furthermore, the scheme is easily extendible to any number of
observers, allowing observation of multipartite nonlocality for a single photon
shared among multiple modes. We also consider the case of atom-photon
entanglement, where the loss threshold can be lowered further, as well as local
filters compensating transmission and coupling inefficiencies at the source.
