RV semi-amplitudes of all known short-period sdB binaries with spectroscopic solutions plotted against their orbital periods (light grey: WD companions, grey: dM companion, dark grey: unknown companion type). The binaries from the MUCHFUSS programme are marked with triangles, binaries taken from the literature with circles. The lines mark the regions to the right where the minimum companion masses derived from the binary mass function (assuming 0.47 M_⊙ for the sdBs) exceed certain values.