bmx saddles...
 

that have rails, of course - are they standard width? Or are they a special bmx seatpost only size?

Standard width, but the problem you will run into is that freestyle seats have oversized rails.

Yeah the oversized rails can be an issue, like I have an odyssey aiken saddle on a thomson post, it works, but can be a little bit of an issue.

cool, thanks.
I really want one of these and would be putting it on a thompson post... maybe i'll take a chance and see if i can make it work.

the rails are a lil wider,so you have to squeez them together until you get the seatpost in place.

Courting sexual dysfunction in later years, or just fashionably insipid?