Move over Facebook, the Winklevoss twins have their eyes set on another digital prize. The twins, both ardent supporters of the online currency Bitcoin, have now announced that they are planning an IPO for a bitcoin-based exchange-traded fund.

For those not up to date on the latest technology, bitcoins are known as a "cryptocurrency" and were developed back in 2009 as a way to transfer wealth electronically, and perhaps most important, anonymously. Since that time a single bitcoin has soared in value from mere pennies to $89 each.

"Investing in Bitcoin has been a whiteknuckle ride so far, and nothing in its near future points to a different trajectory," Nicholas Colas, chief market strategist at ConvergEx, said recently.

The Winklevoss twins are now attempting to create an exchange-traded fund that will be based on the currency. Each stock in Bitcoin would be tied closely to its current value. The Winklevoss twins note that this will allow for people to easily enter the Bitcoin market without having to directly invest in the currency.

"This is not a fad," says Jon Matonis, a board member of the nonprofit Bitcoin Foundation, created last year to foster and protect the system. "It's based on sound security technology, and it has a lot of the same economic properties as gold. It is digital gold."

Many people look at Bitcoin as a sound investment during uncertain economic times. It has been spurred largely by the lack of trust in the American and European government's ability to maintain a balanced budget. The current United States debt resides in the astronomical range of nearly $17 trillion.

"If I understand it correctly the USA is still running deficits of $1.2 trillion per year, or $100 billion per month," says Bill Tai, general partner at Charles River Ventures. "What does that say about the sustainability of our currency? Maybe Bitcoin or other real currencies are not a bad idea as an alternative to hold."

The ETF might be a good thing for Bitcoin. It is currently a very complicated and technological process to obtain Bitcoins, but by virtue of it being on a stock exchange, people will be able to speculate on Bitcoin without having to necessarily go through the hassle of acquiring it.