[sanddrag]

One thing you could do (theoretically) to shorten a takeoff or landing distance is to create a nice strong headwind along the runway. The airplane would maintain enough of a speed difference with relation to the air to maintain lift, but you could theoretically have it with zero speed in relation to the ground. You could takeoff and land while not moving in relation to the ground. You could even do it going backwards in relation to the ground. (I've done this on my RC flight simulator program and it is great fun).

However, flying a plane in any sort of strong wind is tricky and it would be difficult to construct an apparatus to move such a large volume of air at such a high velocity to create this artificial headwind.