Do rear spoilers exist that will usefully reduce spray deposition on the tailgate?

If so, what do they look like?

TIA

There is one as standard on the VRS, but trust me, it does diddly squat at reducing road spray/muck on the back window!!

Even Mud flaps don't stop it...........

Have a look here. :(

It does however keep the raindrops off the window when stopped at traffic lights. Besides it looks the biz !

They look like this:

http://www.tirerack.com/accessories/piaa/super_sporza_splr_bk.jsp

On a more serious note I'd suggest rear mud guards and thats about all you will do I think, since when i used to drive an estate most of the spray came from my own rear wheels with very little you can do to fix it.

Cheers guys, it's rather as I thought then, and my car already has rear mud flaps!

If you are after better rear visibility, an application of Rain-X on the back window helps a little bit.

http://www.halfords.com/webapp/wcs/stores/servlet/ProductDisplay?storeId=10001&langId=-1&catalogId=10151&productId=222433&categoryId=31293

Cheers Andy, I'd thought of that, but it seems to be spray deposition, which suggests that there's not much airflow over the tailgate, and I know RainX needs airflow to work (and I've done the front screen).