Bow Wow -- I'm Selling My Spaceship on Wheels

Bow Wow's selling a car that could easily have been part of the upcoming "Star Wars" flick.

It's a 2014 BMW i8. It could be yours for around $150k. As for why he's selling it, BW needs to make room in his garage for his brand new Range Rover Autobiography.

The rapper shouldn't have much trouble unloading it at GoXmotors ... it has a carbon fiber body, cool scissor doors, and it goes 0 to 60 in 3.6 secs. -- all that and it's a plug-in hybrid to boot.

And it comes with floor mats!