For backpacking purposes, some carry something like this:

http://www.gransfors.com/htm_eng/produkter/new_prod/p_lillayxa.html

This is a very small hatchet and is best used for splitting small kindling. However, you can do the same thing with a fixed blade knife and a wooden baton (i.e. a big stick)

Here is one made by Fiskars:
http://www.fiskars.com/webapp/wcs/stores...p;page=products

Gerber:
http://www.gerberstore.com/index.php?xpage=itempage&xid=427

Remember, a ax or hatchet is a tool, and like any tool, you need to use the right tool for the job. As Dryer has pointed out, shears and saws are more efficient. But personally, I like working with a small hatchet. I usually take them all if I am doing trail work or car camping. If just backpacking, it is a just a small knife. I do have one of those Opinel knives that Phat uses or I may carry a Mora. I always have my small SAK pen knife.

Here is a sample of a good saw:
http://www.fiskars.com/webapp/wcs/stores...p;page=products

You realize, we've opened up a huge can of worms. <img src="/forums/images/graemlins/smile.gif" alt="" />