  The high-resolution setup of the AAOmega spectrograph on the Anglo-Australian
Telescope makes it a beautiful radial velocity machine, with which one can
measure velocities of up to 350-360 stars per exposure to +/-1--2 km/s in a
2-degree field of view. Here we present three case studies of star cluster
kinematics, each based on data obtained on three nights in February 2008. The
specific aims included: (i) cluster membership determination for NGC 2451A and
B, two nearby open clusters in the same line-of-sight; (ii) a study of possible
membership of the planetary nebula NGC 2438 in the open cluster M46; and (iii)
the radial velocity dispersion of M4 and NGC 6144, a pair of two globular
clusters near Antares. The results which came out of only three nights of AAT
time illustrate very nicely the potential of the instrument and, for example,
how quickly one can resolve decades of contradiction in less than two hours of
net observing time.
