  To study the variability of the 523 B and Be stars observed in the Magellanic
clouds with the VLT-FLAMES, we cross-matched the stars of our sample with the
photometric database MACHO, which provides for each star an 8 years lightcurve.
We searched for long, medium, and short-term periodicity and found the
eclipsing binaries in our sample. For these stars, combining, spectroscopy and
photometry, we were able to provide information on several systems of stars
(systemic velocities, ratios of masses, etc). We also present the ratios of
B-binaries to B-non binaries in the LMC/SMC in comparison with the MW. Note
that this ratio is also an important issue to understand the mechanism of
star-formation at low metallicity. We also found the first multiperiodic B and
Be stars in the SMC, in particular the first SMC Beta Cep and SPB, while,
according to the models, pulsations were not foreseen in low metallicity
environments, i.e. typically in the SMC. Our results show that the instability
strips are shifted towards higher temperatures in comparison with the Milky
Way' strips of pulsating B-type stars. By the fact that we found more pulsating
Be stars than pulsating B stars in the SMC, it seems that the fast rotation
favours the presence of pulsations. However, the ratio of pulsating B-type
stars to "non"-pulsating B-type stars at low metallicity is lower than at high
metallicity.
