The modern world is a kaleidoscope of electronic gadgets and systems that make possible things we only dreamed about as kids. Thanks to our electronic world, you can buy a house from your cellphone, see what the night sky looks like in real time on the other side of the world, or profit from nanosecond differences in trading times in the stock market. All before you get out of bed.

Just like my “modern” guitar friends, many people seem to take it for granted that the digital systems that underlie these miracles – the Internet, for example – are eternal. So when I hear someone make plans that assume uninterrupted connectivity, I think to myself: “What if the power goes off?”

Which brings me to one of the most frightening ideas I’ve come across in a while.

A U.S. tech giant is reportedly working on a software platform based on the infamous digital currency “Bitcoin.” The idea is to make it possible for major currencies like the dollar or euro to operate like Bitcoins. Anyone could transact with anyone else in the world directly, bypassing banks completely. Just log on, send your money and you’re done.

This promises a world with no banks, no fees and no hassles… but lots of danger.

Everyone knows that counterfeiting is a risk with paper money. That’s why individual bills have serial numbers on them. But the same applies to digital currencies. Unlike physical money, the electronic files that represent digital currency can be duplicated exactly, with no trace. Since spending a digital dollar doesn’t delete the electronic data that represents it, and in the absence of banks and their accounting systems, some other way is needed to prevent that dollar from being used again by the same person – so-called “double-spending.”

Bitcoin accomplishes this by means of a “block chain.” Every few minutes, a group of all recent Bitcoin transactions is created, called a block. This block is then quickly distributed across the Bitcoin system, where it is added to the ongoing chain of all Bitcoin transactions (hence the name). That way, if someone who has already spent a given Bitcoin (and has not received it back legitimately from a third party) tries to spend it again, the system will reject it as “counterfeit.”

Bitcoin accomplishes this by using a distributed system of anonymous “nodes” that keep track of the block chain. But the same thing could be accomplished by a central server. The tech company working on its own digital currency has therefore floated the idea of turning dollars and other currencies into digital form – with the central server controlled by central banks.

I don’t need to tell you what would happen under this system if the power goes out: No moolah. Of course, the same thing can and does happen now, with so much of our transacting done by credit or debit cards. But at least we have the option of keeping and using cash.

Am I paranoid in thinking that, no matter what the advantages of digital currencies – and bypassing banks is really tempting – the real danger isn’t power outages, but rather giving a central power the ability to turn our money on and off? The dangers of digital currency aren’t small. After all, imagine the opportunities for monetary mayhem: digital wealth confiscation… automatic taxation… courts issuing warrants to seize your digital money…

Nope. I’m a realist. I know that if companies have the power to do that, they will use it.

Yet another reason to stock up on gold, my friends… the ultimate store of value. So far, at least, nobody’s come up with a way to turn off its power.