Andrews Aerospace Mini-Mag Orion
Hi SDF
Somewhat more feasible is Andrews' Mini-Mag Orion which uses electromagnetic compression to push sub-critical fission charges into criticality, and directs the exhaust with the field. Since each pulse unit is sub-critical it avoids possible 'nuclear bomb' issues - a z-pinch isn't an easily portable terrorist device, for example.
Yet I reckon we'll need antimatter spiking for advanced fusion-fission reactions like p+B11 or Li6+Li6. Pure antimatter is probably a futile chimaera, but using it for triggering other reactions will be useful.
Adam