Dijkstra's algorythm was used in router paths if I remember right (dear god, my memory scares me). A* is the best to use for games because it is very accurate and also very fast compared to the other options. Precalculated paths using A* can increase performance by not doing the calculations in-game (which leaves you with a static, unchanging path table). Another option is to go with D* (Dynamic A*), it's a touch slower but allows much more dynamics.

-Rhuarc