4 alternatives that were not yet mentioned. They are all very affordable:
The Boker Plus Trance and (bigger blade) M-Type. Clever, very flat and thin framelock designs by Chad Los Banos. Really pretty sweet.
The traditional way, very very cool knives:
- The French Douk-Douk, scarily sharp and very thin slipjoint, and so much character:
- The German Mercator knife, a very thin and very sharp backlock. It's possible that your grand-grand-father carrier this, and it's still being produced:
EDIT: if these knives seem attractive to you, well I have made short video reviews about them, so you can see them in the hand etc.
Here is a clip about the Bokers, and
here is a clip about the Douk-douk and Mercator.
When it comes to modern designs, I agree with the recommendation of the Spyderco Stretch, I do prefer it over an Endura (which is lovely as well).