With the recent explosion in the price of Bitcoin and other digital currencies, and the massive influx of new altcoins, new investors, and new speculators, the Internet has been rife with stories about people who have made some serious money off the back of this sudden and unanticipated spike in interest. However, as is so often the case, the people who are really raking in the money, are those who provide the services involved in buying, selling, trading, and transferring the altcoins in the first place. A recent report from notable technology blog, Recode, showed that Coinbase (one of the more reputable and established online cryptocurrency exchanges in operation) generated a revenue in excess of $1 billion in 2017, solely on the back of its transaction fees. Much of that revenue, of course, was created by a late surge in the value of Bitcoin, generating that influx of new blood into the market that we have already discussed. This has a knock on effect amongst new and existing traders, driving up trading volume and, by default, the number and size of transactions, each of which attracts its own fee for the exchange.Compared to a more established exchange like TD Ameritrade, who pulled in around $1.76 billion over the same period, and it seems little to crow about, until you consider that Ameritrade’s portfolio covers all manner of stocks, shares, assets, and commodities, whilst Coinbase is making a little under 60% of their revenue dealing solely in cryptocurrencies. Of course, much of that is down to Coinbase’s fees model. Whereas most online stockbrokers charge a flat fee per transaction, regardless of the size, Coinbase has opted for a percentage of the value of the transaction. Again, with the recent spike of interest in Bitcoin pushing the digital currencies values to almost $20,000 per coin at one point, every transaction and purchase is netting the exchange a healthy fee. Both models rely on volume, with the Ameritrade version based on the number of transactions it can perform, and Coinbase reliant more on the value of said transactions. How the recent drop-off in cryptocurrency will affect them in the long run, remains to be seen.