i didnt use this, but i'v scammed 2 mw2's (1 vac banned) And a black ops

my way was:
search a victim who sells shit on a website or forum.
let him pay with paypal
make a gmail account (doesnt matter what kind of username)
go to setting and edit ur name, change it to
Service@PayPal.com or whatever
create a real-looking mail from paypal witch tells the the mony will come in 24-48 hours, and from the "buyers" mail adress send a message that u payed
and if ur lucky u wil obtain the steam username+password

and the secret questions and shit. then u can sell the steam accounts somewhere (school)
/EDIT
people are stupid, if ur paypal mail looks nice, they wont check the headers!!