Something very interesting is going on with Ethereum (ETH 3.60%) right now. Small, relatively unknown companies are starting to add Ether, the native coin of the Ethereum blockchain, to their balance sheets as part of a new strategy designed to lift their stock market valuations. And so far, it's working.Case in point: during the past 30 days, shares of SharpLink Gaming (SBET -20.22%) are up a whopping 150% (as of July 18). SharpLink Gaming has attracted so much attention with its new crypto strategy that i ...