  We study two different superconductor-ferromagnet (S/F) structures. We
consider first a Josephson junction which consists of two S/F bilayers
separated by an insulating layer. We show that for an antiparallel alignment of
the magnetization in the two F layers the Josephson critical current $I_c$
increases with increasing exchange field $h$. The second system we consider is
a S/F structure with a local inhomogeneity of the magnetization in the
ferromagnet near the S/F interface. Due to the proximity effect not only a
singlet but also a triplet component of the superconducting condensate is
induced in the ferromagnet. The latter penetrates over the length
$\sqrt{D/\epsilon}$ ($D$ is the diffusion coefficient and $\epsilon$ the
energy). In the case of temperatures of the order of the Thouless energy this
length is comparable to the length of the ferromagnet. This long-range
penetration leads to a significant increase of the ferromagnet conductance
below the superconducting critical temperature $T_c$. Contrary to the case of
the singlet component, the contribution to the conductance due to the odd
triplet component is not zero at $T = 0$ and $V = 0$ ($V$ is the voltage) and
decays with increasing temperature T in a monotonic way
