Elon Musk is too busy running both SpaceX and Tesla Motors to be worrying about making his Hyperloop concept a reality, which is why he decided to open-source the idea and allow other companies to pursue their own Hyperloop projects. The most promising of these projects comes from a company called Hyperloop Transportation Technologies, which has announced that a prototype Hyperloop track will begin construction in California in about two to three weeks, which will cost around $150 million to build and is expected to take 32 months to finish.