I just got a Spyderco Salt 1 and am very impressed. Besides being totally rustproof, one of the things I like about it is the high-visibility handle. That can come in handy when doing a last-minute spot check before leaving your campsite. Here's a long, boring video of me cutting some stuff with it and comparing it to my venerable EDC Delica 4.
I know there are a lot of people who prefer fixed-blade knives but I like the compactness of folders and find they're more than adequate for most basic backpacking tasks. What do you carry? Are you a fellow Spyderco fan?