A well made survival fixed knife:
 

I have been a fan of Busse knives for a while, their INFI steel is out of this world. It is well balanced for hard and crazy abuse. If you have a well planned out survival bag then I think an INFI knife belong somewhere in that bag. Yes they are a bit pricey but they are (to me) the best production knife company out there right now. They stand behind their product, if you break it they replace it! Their knives hold an edge very well. they are also very rust resistant for a non stainless steel blade. They are tough enough for me to bet my knife on one. It can basically do anything that you will ever think about doing with a knife.

Here is one of their knife put to the test:

http://www.knifetests.com/BussefFFBMtestpage.html

See it for yourself.

The only problem with Busse is really the lack of availability of their product. You have to wait for months for one. They don't charge until they are ready to ship.