I was out with friends last night and we went into a sci-fi bar where they have props and models all over the place. We had fun identifying all the ships, costumes and stuff, but one model had us stumped, and the person behind the bar wouldn't tell us, saying we'd have to find out by other means, and there would be a free drink in it for us if we could - apparently only one person has ever correctly guessed it in two years.
Unfortunately my mad Googling ran the battery down on my phone so I couldn't get a photo, but I quickly whipped this fairly close approximation of it on my iPad when I got home. I think the curved end is the front and I'm fairly certain it's not: a Cylon vessel, Dengar's ship, anything from Independence Day, Dune or StarGate, not Space 1999 or UFO, not any of the Aliens or Star Wars films, or Manta Force.
I have found a photo of it online (someone asking the exact same question over 6 years ago - never got an answer). As you can see it's a lot more "blocky" than some of the other answers, which are close, but sadly not right...
Looking on the virtual tour for the Manchester bar we can see a few other low quality images of the ship.