@ForexGump, not at this time.
Our focus is on offering margin trading (AKA trading with leverage) on the most liquid currencies (along with CFDs outside the US). The key word here is "liquid".
"There was approximately $1.54 trillion in circulation as of April 5, 2017, of which $1.49 trillion was in Federal Reserve notes." https://www.federalreserve.gov/faqs/currency_12773.htm
By contrast, the total market capitalization of Bitcoin is about $44 billion dollars, and the market cap of Ethereum is about $30 billion dollars at the time of this post: https://coinmarketcap.com/currencies/views/all/
Is it any wonder then that a multi-million dollar sell order could trigger a flash crash in Ethereum?
Even before this latest incident, we've seen the price of Bitcoin recently drop more than 16% in one day: http://www.cnbc.com/2017/06/12/now-bitcoin-is-crashing-along-with-the-drop-in-technology-stocks.html
On such a price move in Bitcoin, someone trading on margin could see their account wiped out using only 6:1 leverage. By contrast, the average daily volatility in EUR/USD is 0.63% at the time of this post: https://www.mataf.net/en/forex/tools/volatility
That's why FOREX.com can offer up to 50:1 leverage in the US (in compliance with CFTC regulations) and even higher outside the US for major currencies (less for exotic currencies).
Leverage magnifies gains and losses, so it's important to evaluate the volatility in price for a particular currency before trading it with leverage. This is exponentially true for cryptocurrencies as we have seen recently!