Visible crew/equipment: When the crew are in their sleeping quarters, and Rimmer is talking to the others, a blue boom mic can be seen hovering over his head (you can see this if you watch the dvd on your pc, as some tv's can cut off the edge of the picture) (00:03:10)
Continuity mistake: When Holly interrupts Rimmer learning Esperanto saying "The menu looks interesting", he appears on the TV screen, with his chin blocked by the edge of the frame. The shot then cuts to a view of the screen, and his entire face is suddenly fully in the frame. (00:05:00)
Continuity mistake: When Lister is getting ready, he pulls his trousers off the table, causing the boot on the table to wobble. In the next shot, the boot is entirely still. (00:10:35)
Answer: It's Queen Victoria, someone any Englishman would recognize, and needed no introduction.