As time goes on, Elon Musk's futuristic Hyperloop concept seems less far out, especially as plans for high speed rail in places like California struggle to become reality. 

Last week, the Los Angeles Times reported that the state's planned bullet train will need to be delayed by three years thanks to complications involving funding and the difficulty of tunneling through the Southern California mountains, meaning the first leg from San Jose to California's central valley could be completed by 2025.

That timeframe could be very interesting if the few privately-funded Hyperloop startups manage to build a business beyond the test tracks of the futuristic transport that are being constructed right now.

"Hyperloop will be operational, somewhere in the world, by 2020," Shervin Pishevar, co-founder and chairman of Los Angeles-based Hyperloop Technologies, told CNBC. "We will move people and cargo at 700 miles per hour. That changes the way the global economy works."

Less than three years since Elon Musk open-sourced his white paper describing the Hyperloop, which basically moves pods through closed pneumatic tubes at high speed, Hyperloop Technologies is now building a short test track at an industrial park in North Las Vegas, Nevada with the goal of accelerating a test vehicle from 0 - 335 miles per hour in just two seconds. 

A completely separate startup, Hyperloop Transportation Technologies, plans to build a full scale Hyperloop this year in the planned community of Quay Valley, in California's central valley. While the track will only be five miles long in total, it should eventually be able to carry passengers, offering a real-world test for the technology. 

While the Hyperloop's technology could be ready for passengers before high-speed rail in California, the slower bullet train has something that no Hyperloop project does -- land rights to build a track connecting the state's two major population centers. ?

Hyperloop is privately funded so far, but counter-intuitively it lends itself to being more of a public project, arguably even more than a publicly-funded high-speed rail, which has to follow all kinds of government regulations and procurement rules. 

Since Musk open-sourced his blueprints, a community of engineers and crowdfunders has begun to coalesce around the technology, with one design even coming together via Reddit.

For his part, Elon Musk and SpaceX aren't developing a Hyperloop, but are sponsoring a competition to build the best pod for the system. That competition took place earlier this year and a number of teams were selected to test their human-scale pods this summer at a one-mile test track at SpaceX headquarters. The Reddit-based team is among those that will be testing a pod. 

If you're thinking that perhaps the state should just switch to building a Hyperloop instead of the rail project, don't get your hopes up. Substantial public investment and bureaucracy has already been mobilized to get high-speed rail off the ground, and scrapping all that for an as-yet unproven technology that still sounds a little nuts when you explain it to someone for the first time, well... just don't get your hopes up, Hyperloop fans.

But this doesn't mean Hyperloop doesn't have a role to play in the future of transportation. It could actually make more sense in less seismically-active parts of the country like Texas, and Hyperloop Technologies is betting that it might make sense to build a Hyperloop for cargo transportation purposes. 

By 2025 passengers might be moving around California on bullet trains while goods criss-cross the Central Valley in Hyperloop pods at speeds three-times faster than high-speed rail.