Well sometimes a folder is all you have...
To me the answer is obvious: The best folder I have ever owned, including some $500 ones, and it's $25. Kershaw RJ Martin Tactical 1986, 3 11/16" blade: What puts this one over the top is that it has Kershaw's clever assisted opening (a spring inside one of the scales), and it simply beats all other folders in ease and speed of opening: It basically is an automatic, but without any of the stress and hassles of an automatic... Plus the handle ergonomics are superb, and the edge geometry quite easy to reduce in angle. Lighter than any other yet strong where it needs to be.
Gaston