its possible to download a file by falsifying mime type but you can not read it. you might also wind up in jail doing it. you cannot view the contents of someone’s computer without hacking into it. if you want to track someone without cookies look into the use of Etags and other header tages

there are java scripts which can make a user think the contents of their computer is being viewed on line but it is only seen on the local computer .by clicking on a link that points to a folder on the local computer much like typing the location in the address bar (hope i explained that ok)