Most functional jetpacks aren't really jetpacks. They're rocket belts, or ducted-fanpacks. To make an actual jetpack, you need some jet engines, and two guys have stuck four (barely) hobby-grade engines together into what they hope will become a working strap-on flying device.
Each of these micro jet turbine engines produces 100 pounds of thrust, meaning that four of 'em together can get even a hefty human up off the ground. They run on regular old Jet A fuel, instead of something absurdly dangerous and expensive like hydrogen peroxide, meaning that the operating cost will be about $4 per four minute flight instead of $1,400 for just 30 seconds of airtime.
The good news about this Kickstarter is that these dudes only need $30,000 to make their jetpack happen. The bad news is that even if they're successful, none of the pledge levels will even put you on a waiting list for a jetpack of your own. For $5,000, you can take a tethered flight, but rather than being the prototype for an affordable jetpack for the betterment of humanity, this one-off is only intended for "flying in large scale special events (ie: Super Bowl, Olympic Ceremonies, etc.)." I guess it's not really the future yet, huh.