Rewrite of the Markshire Climbing system (http://nwvault.ign.com/View.php?view=nwn2scripts.detail&id=103) into a jumping system. There's not a whole lot of Markshire code left.
Included demo area includes jumping to a waypoint destination, and jumping dynamically around at area based on player facing. Dynamic jumping is blocked by sufficient obstruction, or lack of a line of sight to the destination. Falling damage is calculated how far you fall on the z axis (in other words, it reads from the actual map and determines the distance of the fall. Jumping/falling is handled per d20 srd rules for jumping and falling.
The dynamic jumping would be suitable for implementation as a feat, presumably with some sort of cooldown. You'd probably want to make the player select a destination, and could use some of the DC code from the waypoint jump function to determine the DC.
Technically, the pc doesn't actually jump and inhabit the space of the path. The code for dynamic jumping looks for obstructions in the determined path of the jump, and won't jump if there's too many invalid locations in between, or if the jumper's line of sight is blocked (there are included messages for each).
youtube video showing directional jumping:
early video, shows targetted jump and illustrated the bug mentioned above