The main result asserts the existence of noncontractible
periodic orbits for compactly supported time-dependent
Hamiltonian systems on the unit cotangent bundle of the torus
or of a negatively curved manifold whenever the generating
Hamiltonian is sufficiently large over the zero section. The
proof is based on Floer homology and on the notion of a
relative symplectic capacity. Applications include results
about propagation properties of sequential Hamiltonian
systems, periodic orbits on hypersurfaces, Hamiltonian circle
actions, and smooth Lagrangian skeletons in Stein
manifolds.