My grandfather had a train in his attic.
It was a toy electric train, of course, and the track was nailed down to the floorboards in a figure 8, with a span of plastic trestles so the tracks went both over and under themselves, as you can see in the picture. I remember climbing the pull-down metal steps to play with the train with my grandfather--"Pa" to me, the same thing my own children call my father--and being captivated not only by the train, but by the other things that lived there: a pink plastic baby crib (whose headboard you can glimpse in this picture, nestled in the floor joists just behind me and to the left), and my uncle Danny's model airplanes (the kind that really fly), and Christmas decorations (except in December, of course), and countless things I know where there but which, try as I might, I just can't quite picture now. There may have been a permanent light fixture attached to the ceiling joists or rafters somewhere, but the light source I remember was a small lamp with a little decorated glass shade that sat on the floor, and which I turned on by rotating a delicate key-like switch.
Pa had a little bottle of magic solution that could be put into the locomotive's smokestack, a couple of drops at a time, to make the engine really smoke! To an eight-year-old boy in 1975, that was pretty impressive.
Though he died when I was only eleven, I have many memories of my grandfather. I remember having a discussion with him up in that attic about the meanings of words--apparently an interest of mine even when I was very young--in which he explained to me that "a few" was just three or four, but "several" could get "way on up there, seventeen or eighteen." Even though I haven't heard his voice in thirty-seven years, I swear I can hear exactly what he sounded like when he told me this.
Attics have fascinated me for as long as I can remember, and this is why.