I'm currently enamored with slabs of petrified wood.
Petrified wood is the remains of fossilized vegetation and trees. It is the result of a tree having turned completely into stone by underground decomposition, when wood becomes buried under sediment and lava. Due to a lack of oxygen the tree turns to stone yet retains it's original wood look.
Petrified wood can be harvested all over the world but the larger tree diameters make the best and most exotic slabs. It is a very masculine and timeless finish that can transform any design.
And if your budget does not allow for a slab, you can always find the small petrified wood pieces and use it as a small side table.