Antimatter Annihilation Engine

Closer than ever to reality! Recent reports have indicated that scientists have succeeded in trapping antihydrogen in strong magnetic fields. Although the time of storage was very minimal (mere milliseconds), it's a positive step towards being able to store antimatter for longer periods of time, an important design consideration for a practical antimatter annihilation based engine. In addition to the storage requirement, methods of economical mass production of antimatter need to be developed. But this might simply accomplished by putting more energy into production (ie powering a particle accelerator with solar power transmission). The actual annihilation part is easy...