  In this paper we review the coset construction for winding subalgebras of
affine Lie algebras. We classify all cosets of central charge $\hat c<1$ and
calculate their branching rules. The corresponding character identities give
certain `doubling formulae' for the affine characters. We discuss some
applications of our construction, in particular we find a simple proof of a
crucial identity needed for the computation of the level-2 root multiplicities
of the hyperbolic Kac-Moody algebra $E_{10}$.
