I like to carry thin knives too. I love and have already sung the praises of the the mercator k55, my usual edc, especially when i don't want to lose/mess up a more expensive blade. I carry mine tip up in the watch pocket of my jeans, i can flick it open one handed and close it one handed as well, although closing is more awkward. I also trust the lock, can't see it failing unless you did something crazy. Another excellent choice (that I'm surprised nobody beat me to) i feel would be a stainless handled Endura, it's much thinner than the frn handled ones. A little heavy, which i like. i appreciate the stouter blade sometimes as well, but sometimes i wish FFG was an option on the stainless ones.