Mora Companion or Opinel #8. I have both. Both inexpensive, both very light to carry.

The Mora is near impossible to break and at about 4.1 ounces is lighter than most "survival" type fixed blades. It will do everything you need of a camping knife.

The Opinel #8 is about the same size but is only 2.6 ounces. If you choose the Opinel, i recommend the number 8 because you get very large bade for not much weight penalty. It is even big even to baton with in an emergency (i've never abuse my knife to that extreme, but there are youtube vids of ppl doing it). Wood floats but also swells, so if you do a lot of water activities, that may be a consideration. The wood handle isn't as grippy and can be a pita to clean. The Opinel looks less threatening because it is an old world knife.

Get both =)