The Register: "Some bright empiricist from Root-Core has discovered that anyone can log into their Hotmail account and then call messages
from any other Hotmail account by crafting a URL with the second account's username and a valid message number.
Finding a valid message number is of course total guesswork, but they all follow a consistent format and always have the same
number of digits (i.e., a time stamp), so with the help of a little brute-force progie one can try numerous combinations in the
background rather than type them in."