Certain aspects of the Star Wars universe (FTL travel, force magic) are clearly impossible. But some technologies, like extremely high-powered thrusters and even lightsabres, may one day be feasible.
This month, Michigan State University released "Chillin' with Chewie," a 5-video series in which everyone's favourite Wookie warrior interviews a range of experts about all sort of fabled Star Wars technologies to learn whether they are scientifically plausible and how soon we can expect to have them. The Wookie's inability to speak human languages notwithstanding, his interviews are surprisingly informative.
My personal favourite is this video on propulsion systems -- I had no idea a TIE fighters' thrusters are a million times more powerful than anything we've ever developed -- but you can check out the entire series here.