More after the break...
Jayne's most famous hat, the hat knitted for him by his mother and sent to him in The Message, is an orange-colored hat with a large pompom on top.
More screencaps from The Message:
The best site I've seen that covers Jayne's Hat is this Squidoo page. They do sell a version of this hat at ThinkGeek. There are a bunch of people over on Etsy that make and sell their versions as well. Knitting Freak has a little tutorial on how to make your own.
Next hat up is Jayne's cowboy hat.
This screencap is from Heart of Gold. He also has it on in Our Mrs. Reynolds:
He wears a similar hat in War Stories:
And in Shindig:
Finally, he wears an ear flap hat:
From The Train Job.
And, to disguise himself in Jaynestown:
And in Trash:
My Photobucket Album for Jayne.
Serenifly Costumes site for Jayne.