All those people buying the Saturn V for their kids... I bought it for myself because, er, well, let's just say that the Apollo launches were one of the Grand Stunts of the 20th century, and when the Lego Store about a mile from home had it in the window, well, er, how were you going to keep me away from it? (For reference, I'll be 52 in a few weeks.)
I even weighed it. It turns out to be about three quarters of the right scale weight for a fully fuelled real one. That is, if you scaled it up to the true height of the original, the model would weigh about 2250 tonnes instead of the original's 3000.
I think that might be showing off my outer geek, though.