Particle physicists working on colliding beam experiments are often faced with a dilemma. The study of rare processes requires high luminosity and hence the introduction of magnets close to the interaction point to focus the beams down to the smallest possible transverse dimensions. The space occupied by these magnets is not available for tracking devices or calorimeters and the acceptance of the detector therefore suffers: experiments have historically been able to have either the largest possible acceptance or the highest luminosity, but not both. The aim of this proposal is to at least partially resolve this dilemma by studying combined function magnets/calorimeters or magcals. These devices could be used to provide the necessary focussing close to the interaction point without compromising the experimental acceptance. They could also perhaps replace the solenoid typically used to provide the experiment's magnetic field, thereby reducing the amount of dead material these represent before or within the electromagnetic and hadronic calorimeters.