Sails for kayaks

Has anyone purchased one of those sails for kayaks?
How do they work for you... or are they more of a hassle than anything else?

Hi Doty,
I've used and reviewed the WindPaddle sails and found them useful. They're not a hassle. They store easily and sail well.

You can read the review and related info at:
http://paddlingtravelers.blogspot.com/search/label/ kayak%20sailing

Awesome link, thanks.

Thanks for the post on kayak sails.
There's only one problem with these things: you still need to hang on to your paddle for bracing and steering, unless your kayak has a rudder, which my Necky Manitou 13 does not.

So, how do you manipulate and play around with the sail and still use your paddle for navigation? Can't be done ... unless you're a paddler with four arms!

It's not as tough as you think.

You set the sail for either downwind or crosswind paddling, tighten the sheets and the sail takes care of itself.

You then use your paddle as a rudder.

No need for four arms. Just two. The sail is controlled by the sheets, not your hands.

Can you sail upstream at all?
Can you have a rudder installed on any kayak?