At the bottom, like the SeaQuest knife, another Blackie Collins design, this time a Gerber River Guide knife.
This one clips on my life vest when whitewater canoeing, kayaking or rafting.
Above that is a Bokker switchblade with a circular spring that brings the blade out with a satisfying machine "clunk", sounding very much like chambering a round on my Smith & Wesson 659. Either way, the sound produced is a great conversation stopper and attention getter.
You have to hang onto it as the recoil of opening can make it jump out of your hand if you don't have a good grip. I think the GIF animation earlier in this thread was also a Bokker.
Aerial
EDIT ~ added this:
