Mus musculus, the House Mouse! Another rodent with which I have had personal experience. A family of them made a nest in an empty area behind our kitchen cupboards. When we returned from a trip, we were clued in to their presence by a scattering of chips over a floor cushion, and a chewed chip bag. Then if we stood real still in the dark kitchen, we could hear the pitter patter of little mouse feet working their way through the cupboard woodwork.