  We demonstrate the possibility of studying weakly interacting new particles
in weak boson fusion, using the example of supersymmetric same-sign charginos.
This signal could establish the existence of Majorana neutralinos and give
access to their electroweak couplings. It can be observed over (supersymmetric)
QCD backgrounds provided the charginos are light and not too close to the
squark mass. We finally show how same-sign fermion production can be
distinguished from same-sign scalars or vectors arising in other models of new
physics.
