Hip Hop Slave Sabre

. . . however, surely a component manufacturer would sell shedloads of these if for instance there was a way for the powerpack to live inside the seat post and the film itself could be made more water/world resistant?

It's currently water resistant, it's just my endless messing around with it that caused it's death.

But you are right, it would be trivial (and cheap) for a component manufacturer to design a seatpost with an EL surface and power source inside the post.

. . . even from an aesthetics point of view, that post would look shitloads better than have knogs all over your bike.

You can't say that, Knogs are the Aerospoke of bike lighting, if you keep that kind of talk up there will be a hipster squad sent out to whack you.