The best lay bedding?

Hello, i'm wondering what you use as bedding in laying boxes?

We got chickens not long ago, they are free ranging all day long and they have a nice coop and run area too.

Here is what i found an hour ago in a sheltered barn full of dry leaves, total surprise and happy me! :)
I need to make some laying boxes in the coop and elsewhere on the farm, barn being one of them - let nature show you the way. :)

I guess leaves are good for laying boxes?
What you think?

I use either hay, straw or wood shavings depending on the price and the season. Right now things are kinda muddy and gross and I've been using wood shavings in the boxes as well as outside the boxes to help clean the hen's feet before she lays. Shavings tend to soak up moisture better than leaves or hay so far as I can tell and it's a good medium for composting chicken crap. I used a lot of hay last year and had a bitch of a time getting it all piled up to compost. The long strands of grass were matted with poo and frozen into a block so I had to pile it up as it thawed slowly over a few weeks. I'm thinking that the shavings will perform better as they make a nice carbon sink for the high nitrogen chicken poo.

Leaves are not the best bedding material, but they are free, so I have used them pretty extensively. Someone gave me a bag of fine wood chip animal bedding and I have been using it on the rooster pen, it is very absorbant and does not stink readily, but once the bag runs out I am not likely to replace it. Leaves are so... free. If you sweep a sidewalk where leaves have been crushed by foot traffic then I think their absorbing function as bedding raises slightly.
not to mention some leaves are better than others. Try using magnolia leaves as bedding and you will have some uncomfortable chickens.
I have tried pecan, catalpa, hackberry, ailanthus altissima with workable success.

Ground corn cobs or pine shavings. Other things like grass, leaves, etc. that contain lots of tanins will stain eggs which can prevent you from selling or distributing otherwise perfect eggs.