According to this thread on Reddit (by way of CVG), one poster who remains anonymous claims that he (or she) has managed to make $10,000 from Diablo III virtual item trading using the game's Real Money Auction House.
He published his results on Reddit, using evidence such as screens of PayPal transactions and item trading. He claims to have made $2,700 in 12 days, about $1,600 per week.
"One of my favourite parts of gaming has been the economics of the item markets since I started trading in Neopets ten years ago," he wrote. "It is what first got me interested in economics, and I am now studying business at a good university. I hope to consult with game companies someday about balancing the economies of their games."
The person also claims that his (or her) day job is in the stock market.
While the entire story could be fabricated, we have certainly heard our fair share of anecdotal evidence from Diablo III players (that we know) claiming to have made thousands of dollars selling virtual goods from the game. We hope its true and we hope that that person is swimming in it right now like Scrooge McDuck...
You can read the Reddit thread here.