As far as Runescape stuff, technically no. Because the items "Don't Exist" and "Belong To Jagex, Not You".
But if you're willing to spend money (usually a lot more than your account/gold is even worth) you can eventually track down the scammer and bring him to a court or formal dispute.
The following posts regarding the theft of virtual currencies is incorrect. As far as I am aware, both the US and the majority of countries market it as the following:
Mail/Wire Fraud - "In the United States, mail and wire fraud is any fraudulent scheme to intentionally deprive another of property or honest services via mail or wire communication. It has been a federal crime in the United States since 1872."
I haven't had the time to delve into the legal definition as far as across the pond legal documents, but I assure you, it's roughly the same thing.
Even if the legal system doesn't recognize all virtual currencies, they recognize lots of them (Eve, RS, WoW, SL, and Bitcoins are recognized as having legal value currencies) and stealing information or "services" is considered wire fraud.
Litigation in United States Law:
Whoever, having devised or intending to devise any scheme or artifice to defraud, or for obtaining money or property by means of false or fraudulent pretenses, representations, or promises, transmits or causes to be transmitted by means of wire, radio, or television communication in interstate or foreign commerce, any writings, signs, signals, pictures, or sounds for the purpose of executing such scheme or artifice, shall be fined under this title or imprisoned not more than 20 years, or both. If the violation affects a financial institution, such person shall be fined not more than $1,000,000 or imprisoned not more than 30 years, or both.
So, I find the OP's question irrelevant. Those who were scammed simply need to read into their nation's legal system in terms of fraud and see if their case will hold in court. Theft of virtual goods (considered property, not currency) is already illegal.
The funny thing with fraud is that there are several levels:
Fraud - committing the act
Conspiracy to commit fraud - planning to do the above with another conspirator
Attempted fraud - attempting to do the above and failing