I think the problem with this sort of rubbish, that is far from exclusive to the railways, is that whilst no self respecting enthusiast would consider buying it, they make an idea gift for the enthusiast in your life. It's the sort of thing you put in pride of place when they come to visit, but remove to some dark, hidden location as soon as they leave.
On the subject of "streamlined" railway themed novelty products, the Pendolino and the 395 would both be the ideal shape. I'm sure most people can think of the ovious name for the former too. Javelin says enough as it is. Slogans could relate to tunnels, and that these high speed trains come in record time.