The hot R Coronae Borealis star DY Centauri is a binary
  The remarkable hot R Coronae Borealis star DY Cen is revealed to be the first and only binary system to be found among the R Coronae Borealis (RCB) stars and their likely relatives, including the Extreme Helium stars and the hydrogen-deficient carbon stars. Radial velocity determinations from 1982-2010 have shown DY Cen is a single-lined spectroscopic binary in an eccentric orbit with a period of 39.67 days. It is also one of the hottest and most H-rich member of the class of RCB stars. The system may have evolved from a common-envelope to its current form. 
N. Kameswara Rao, David L. Lambert, D. A. Garcia-Hernandez, C. Simon   Jeffery, Vincent M. Woolf, Barbara McArthur
astro-ph.SR