Without being a leet haxor I've found out some interesting things about people with the same name as myself.
Firstly they, or businesses they deal with, cannot cope with email address containing digits.
Secondly, Americans seem to put all kinds of 'useful' information the the web.
email@example.com keeps forgetting he's number 11 and so I've received information about his home address, his DOB, marital status, the name of his wife, her DOB, the number of children he has, the dates he'll be away from home in another state, the name of the church he goes to, the sports he's a tutor in, the make, model and year of his car, the price he paid for his house, (looks like a nice one) the amount he's paid to the city in taxes for the year, the academic courses he's been on etc. I've also been CCd in any number of emails by his friends meaning I (could) have a nice list of his friends and acquaintances.
All this has dropped into my inbox, I've done nothing to seek it out.
I usually contact the sender and let them know that a mistake has been made and even managed to track down the American theprof to warn him that his confidential info is being sent out to the wrong person.
Yes, putting every last detail on a public notice board is a bad idea but you can't fight stupidity.
Worth a mention: How much information do you think your postman has about you? Name, address, birthday, when you're on holiday, the name of your bank, your employer, the companies you have shares in, your interests. Frightening how much you can learn about someone just by looking at their book-shelf isn't it?