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Seems are obvious, and have been mentioned earlier in the preliminary discussions regarding physiology. From Alien Technology - 1. Biology/Physiology - Part II, take as an example,
a water world where the intelligent species has developed wholly as an underwater organism. Smell, light, and radio waves are not the most effective or efficient means of communication in water, due to the properties of water. But sound is a different matter - sound is a very effective means, which is why whales and dolphins, among others, are able to communicate over long distances (sometimes thousands of miles) via sound alone. Using electricity would be difficult, and so development in that area could be very slow.Other environments would have strong influences on the course and development of alien technology - a planet with much greater gravity, and thicker atmosphere, would struggle more than we to have a rocket escape the planet's gravity well, and to survive the longer and more fiery reentry. On such a planet would Zeppelin type crafts make more sense, or be viable much longer on such a planet compared to Earth?
Or if the alien race lives on a planet with a highly elliptical orbit, or a greatly tilted planetary axis, such that weather conditions vary extremely throughout their year, they may very well be motivated to create technology to help them deal with mitigating the results of the extreme weather patterns, especially if they are a species that wants to expand its territory to cover as much of their planet as possible (life tends to expand to fill its environment as much as possible - life that evolves otherwise would soon end, to be usurped and replaced by life that does strive to expand).
And for aliens that live in a solar system that is more populated by hazardous asteroids than our own system (maybe, for instance, it doesn't have a Jupiter sized planet to clean out many of the asteroids), such that they suffer many more meteor hits on a regular basis than the Earth - such beings would definitely have as one of their priorities technology tools to help them locate, track, and deal with hazardous asteroids.
Of course a large water planet would have some added natural protection - meteor impacts into an ocean are not quite as devastating as the same meteors impacting on the rocky surface of a more Earth-like terrestrial planet. Also, if the planet has a thicker atmosphere, that would give greater protection.
And what of a planet that, for whatever reason, does not have the coal and oil or other such natural energy sources as the Earth? They would be driven to find other means for power to power their technologies, developing solar power sooner, for instance. It would most likely have a strong impact on their transportation technologies as well.
So as with the other categories, we need to sit down and carefully think about the different kinds of physical environments an alien race could grow up in, and we need to include in our contemplations all aspects of the physical environment, even what may, at first, seem insignificant. I think we sometimes forget just how much our environment shapes us, since we are born and raised in it.