A fresh approach to path finding algorithm by NICTA student Daniel Harabor. Looking at his algorithm, it is a modified A* search with extra conditions to make sure that only a unique paths are explored. It checks the next neighbouring space for obstacles, if there are none, then they can be skipped as such a path does not contribute to a unique walk.

It is one of those logical approaches "why didn't someone think of it before". The results are very good and the accompanying screenshots give a nice visual comparison to other approaches:

Would be a good path finding algorithm just for the speed increase. It is claimed as optimal, though I cannot convince myself of that.