I've been encountering more of these hoaxes lately.
I've been looking around for a d700 for a while and came across an ad in gumtree. It was selling for $870. I was just looking around cameramarket and theres 2 listed on the same day both for $700ish.
I did check it out and they wanted me to go through a company called Ukash. It supposedly lets you only release money to the seller after you've receieved the item. Sounds safe doesn't it? but after googling I've read things where they call you directly and act as if they're from the postal service - saying your item has been received. So you release the cash to them... but of course they never send you anything!
Just thought I'd send out a warning and was wondering if there are any other people who have encountered this. I did want to see the camera first to check it out but I never got to that stage.