There is a thing quite similar to this in the messenger options. Options -> privacy. And there just below the boxes with the e-mail addresses there is this button that u can click. It shows who has u on their list. Not a 100% sure way of checking if someone has blocked u but it is handy too.
my friend s got an msn thing that clicks the other person's remote assistance thing then they can take control over your computer using remote assistance.
He did it to me once when i went to the bathroom n when i came back there was a whole bunch u stuff opened n my mouse was movin by itself.