Replying to the original post: These internet scams although a hassle, and a waste of time, and now more common than ever, luckily I find them very easy to spot. I hope no one is actually falling for these scams since they seem to all follow the same pattern: quick replies to ads for bikes (or whatever you happen to be selling) when any reasonable person knows the wares you are selling will usually take a some time to sell. The email is always from someone in a different country, or a friend of a friend or a distant relative, who has tons of money and wants to pay extra for you to accept a wire transfer and send the difference to his friend...etc, etc...you get the point.
Bottom line: if you're selling your bike or parts on the forum, just talk to the person on the phone before exchanging money, or better yet just trust your gut. If the deal sounds too good to be true, it is.