Interest in cryptocurrencies has surged since 2015 as bitcoin has seen its value rise from about $300 per coin to a peak of nearly $20,000 per coin in December 2017, then dropping to about $3,500 per coin as of January 2019. Other cryptocurrencies have seen similar surges and dips in value. More than 2,000 cryptocurrencies are listed on investing, but two of the most popular alternatives to bitcoin include ethereum ($117 per coin, $12.3 billion market cap, as of January 2019) and litecoin ($32, $1.98 billion).