I've started uploading some of the many sounds that I've recorded to FreeSound.org which is a website for sharing atmos and sound effects. This is the haunting sound of a baby crying in a room that was several metres away. I recorded it in a university building hallway after hours. The hallway had many hard surfaces like linoleum so the recording is mostly reverb. The only recording device I had was my phone, but I had to get this sound on tape. I've since used it in a few projects when I've needed something haunting.