1. Mythbusters- Currently 9 seasons. From rigging to electrical engineering to almost a hundred ways to make something go "Boom!", Mythbusters has it all. Adam, Jamie, Grant, Tory, and Kari make an excellent team.
2. Eureka- 4 seasons. Although everything here is science fiction or strictly theoretical, it can be an inspiration to techies.
3. Nova- Various Episodes. Science... really, really interesting science. Even though I wish there were more on Netflix, admittedly I haven't watched every episode currently on it.
4. Extreme Engineering- 4 seasons. Really good shows. The best are projects that have already been made. In those episodes, such as the "Big Dig", the engineers interviewed talk about overcoming real world challenges.
5. How it's Made. 9 seasons. Watch machines hum away to produce everything that you've seen, touched, or heard about in the modern world.