  We propose to realize the anisotropic triangular-lattice Bose-Hubbard model
with positive tunneling matrix elements by using ultracold atoms in an optical
lattice dressed by a fast lattice oscillation. This model exhibits frustrated
antiferromagnetism at experimentally feasible temperatures; it interpolates
between a classical rotor model for weak interaction, and a quantum spin-1/2
$XY$-model in the limit of hard-core bosons. This allows to explore
experimentally gapped spin liquid phases predicted recently [Schmied et al.,
New J. Phys. {\bf 10}, 045017 (2008)].
