Some of the very high energy (VHE) gamma-ray sources detected with the modern
generation of Cherenkov telescopes have been identified with previously known
X-ray binary systems. These detections demonstrate the richness of non-thermal
phenomena in compact galactic objects containing relativistic outflows or winds
produced near black holes and neutron stars. Recently, the well-known
microquasar Cygnus X-3 seems to be associated with a gamma-ray source detected
with AGILE. Here I summarise the main observational results on gamma-ray
emission from X-ray binaries, as well as some of the proposed scenarios to
explain the production of VHE gamma-rays.Comment: 12 pages, 7 figures. Invited talk at the "Fourth Heidelberg
International Symposium on High Energy Gamma-Ray Astronomy 2008