Not the building itself, but the content.
Number 18 rue de la Grosse Tour is a perfectly plain, ordinary looking building. The mini train tour of Tours passes it without comment, but the windows are full of amazing things: what look like structural models in timber, models of tiled roofs, strange items made out of copper and brass. Sculpture? Apprentice pieces?
We don't know - the building is unmarked, the letterboxes are only for the residences above, there is nothing I can find on the interwebs, and we didn't even bother asking at the Tours tourist office (who appear to resent being woken up by silly people asking questions). The pieces perhaps have some connection to the Musée de Compagnonnage, as similar pieces are displayed there.
So there you go - a building full of items that I would willingly offer house space to (and that's a rarity!) and I can find out nothing about it.
The photos were taken at very slow shutter speed, without a flash, with the camera lens pressed against the glass in lieu of a tripod. You can see the reflection of the lens.