  In this paper we introduce a trace-like invariant for the irreducible
representations of a finite dimensional complex Hopf algebra H. We do so by
considering the trace of the map induced by the antipode S on the endomorphisms
End(V) of a self-dual module V. We also compute the values of this trace for
the representations of two non-semisimple Hopf algebras: u_q(sl_2) and
D(H_n(q)), the Drinfeld double of the Taft algebra.
