We demonstrate the common bihamiltonian nature of several integrable systems.
The first one is an elliptic rotator that is an integrable Euler-Arnold top on
the complex group GL(N) for any $N$, whose inertia ellipsiod is related to a
choice of an elliptic curve. Its bihamiltonian structure is provided by the
compatible linear and quadratic Poisson brackets, both of which are governed by
the Belavin-Drinfeld classical elliptic $r$-matrix. We also generalize this
bihamiltonian construction of integrable Euler-Arnold tops to several
infinite-dimensional groups, appearing as certain large $N$ limits of GL(N).
These are the group of a non-commutative torus (NCT) and the group of
symplectomorphisms $SDiff(T^2)$ of the two-dimensional torus. The elliptic
rotator on symplectomorphisms gives an elliptic version of an ideal 2D
hydrodynamics, which turns out to be an integrable system. In particular, we
define the quadratic Poisson algebra on the space of Hamiltonians on $T^2$
depending on two irrational numbers. In conclusion, we quantize the
infinite-dimensional quadratic Poisson algebra in a fashion similar to the
corresponding finite-dimensional case.