there are loads of system like that, this one is bigger so i guess the form factor makes it possible to get some sound on it s own. where the systems i ve seen before wouldn't make a sound if not stuck on a table or a window or a box. any surface that can vibrate or resonate. so a pillow would disappoint you ;)
the idea is to make the surface it s on to vibrate, turning it into a really poor speaker. the sound will greatly depend on the surface.
the only force of such a thing (out of the gadget addiction) is the size factor compared to a speaker.
but then in a situation where you need space and travel, why would anyone take this over a good pair of iem?