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I played this game in the first computer I owned, and it has proved to be one of the most relevant, as time passed. Although it was not because of its quality (I liked it, but it is no Half-Life), but because it introduced a secondary control scheme that I've used in every FPS/TPS since. To the point that I simply refuse to play any shooter which doesn't remap properly to it.

Instead of the typical WASD, it allowed using:
Forward: Right mouse button
Backward: Space
Strafe left: S
Strafe right: D
Fire: Left mouse button
Jump: A
Crouch: C
Use: F

Leaving my index and pinky fingers free for secondary actions (G: Alt fire). It also has the welcome property of being nicer on the space bar, since it is not maniacally hit in platforming scenarios.
I recommend everyone to try that configuration (where possible), and honour Kingpin for trying something different in control schemes.

So, Kingpin will always be a good part of my memories. But I'm not buying it =) Sorry.
Some weird control mapping you have got there :)
I'm using the same mapping as you do Elideb for all my games that supports it. And if it doesn't support I simply don't play it :D I preferre to use my mouse for movement and shooting and my fingers for the other controls.