The digital currency Bitcoin now has a famous backer, the world\u2019s richest person Bill Gates says he finds the virtual currency \u201cexciting\u201d and loves it because it is \u201ccheap\u201d. To have a prestigious Bitcoin advocate can only be good news for the cryptocurrency.\r\n\r\nIn a Bloomberg interview, Mr. Gates said:\r\n\r\n\u201cBitcoin is exciting because it shows how cheap it can be. Bitcoin is better than currency in that you don't have to be physically in the same place. And of course for large transactions currency can get pretty inconvenient.\u201d\r\n\r\nIt is not the first time Bill Gates has praised Bitcoin. In September, he called the virtual currency a tour-de-force (a great feat).\r\n\r\nMr. Gates added, however, that we should be careful because of Bitcoin\u2019s anonymity feature and its alleged usage by terrorists and money launderers.\r\nMr. Gates' comments on Bitcoin will boost the virtual currency's prospects considerably.\r\nFor customers who are not trying to be anonymous, Bitcoin technology is key \u201cand can add to it or you could build a similar technology where there's enough attribution where people feel comfortable that this is nothing to do with terrorism or any type of money laundering," Gates added.\r\n\r\nThe founder of Microsoft believes that all financial transactions will eventually be completely digital, universal and nearly free.\r\nWhat is Bitcoin?\r\nBitcoin is a digital currency that can be sent person-to-person with no need for it to go through a central authority, such as a central bank. Founded in 2008, it was the world\u2019s first totally decentralized digital-payment system that works like \u201conline cash\u201d.\r\n\r\nSatoshi Nakamoto first thought of the idea in a paper he published \u201cBitcoin: A Peer-to-Peer Electronic Cash System.\u201d\r\n\r\nSellers and buyers are protected from fraud when doing a Bitcoin transaction because it is computationally not possible to reverse.\r\nBitcoin payment options spreading\r\nSome major online companies are starting to accept Bitcoin payments for a number of their products.\r\n\r\nOn September 24th, PayPal said it was partnering with Coinbase, BitPay and GoCoin to allow merchants to accept Bitcoins for downloadable music, online games, and some other digital products that are delivered immediately upon payment.\r\n\r\nAt the beginning of September, eBay\u2019s mobile payments provider Braintree said it was working towards allowing Bitcoin payments for Uber and Airbnb purchases.\r\n\r\nIn June, Internet-based travel website company Expedia announced it would accept Bitcoin payments for hotel bookings, initially just in its US website. If all goes well, it will eventually include payments for cruise tickets, rental cars, flights and leisure activities.\r\n\r\nOnline retailer Overstock.com accepts bitcoins. In May, Zynga, the online games company, said it was planning to accept Bitcoins payments for tokens of virtual goods on some online games.\r\n\r\nBloomberg Video - Bitcoin advocate\u00a0Bill Gates explains\r\n\r\nIn an interview on with Erik Schatzker on "Street Smart," Bill Gates comments on Bitcoin.