Electricity transformers; power supply devices (transformers); power supply units (transformers); transformers (electricity); electric power supply units; electric power supply units having stabilised output voltage; power supply apparatus (transformers); power supply devices (transformers); power supply units (transformers); computer games entertainment software; computer games instruments adapted for use with an external display screen or monitor; computer interface cards; computer interface devices; computer keyboards; computer modems; computer monitors; computer mouses; computer peripheral devices; computer printers