Person who reads over the shoulder of another person without their consent, i.e. on trains, buses,etc. Taken from the Greek "lathra" meaning surreptitiously and "anagnostis" meaning reader.

In The Meaning Of Liff, Douglas Adams suggests the word "Corfe" to denote a magazine or newspaper which because more interesting because you're sneakily reading it over someone's shoulder. He also suggests that you can turn your newspaper into a corfe simply by letting someone else read it.