  Let $G$ be a simple and simply connected complex Lie group. We discuss the
moduli space of holomorphic semistable principal $G$ bundles over an elliptic
curve $E$. In particular we give a new proof of a theorem of Looijenga and
Bernshtein-Shvartsman, that the moduli space is a weighted projective space.
The method of proof is to study the deformations of certain unstable bundles
coming from special maximal parabolic subgroups of $G$. We also discuss the
associated automorphism sheaves and universal bundles, as well as the relation
between various universal bundles and spectral covers.
