If you are writing a certain sort of SF, then "antimatter" is great stuff. Back in the real world - it looks about as economical as a hand-dug limestone quarry

If you are writing a certain sort of SF, then "antimatter" is great stuff. Back in the real world - it looks about as economical as a hand-dug limestone quarry on top of Mt. Everest, and about as safe as nitroglycerine-powered cars.