In the satellite array with the ghoul scientist you get the sat codes, and coordinates from the computer, who are you supposed to use them on, i remember when i first played fallout 3 20 times before i did launch them but they fell right outside the complex. I'm just playing the game again, figured i would do all the little things i didn't do before.

The Highwater Trousers' activation codes just allow you to bombard the surrounding area from the Satellite.

The coordinates just mark other Satcom towers in the area.

No big quest, just a nice little backstory with Ghoul. And random destruction.

well i went into the military place where you have to have the 3 keys to get into, cant remember the name right off hand, it is where you pick up the t-59 , 56 , 57 think it is, anyway there is a computer that says you can launch an icbm i guess the one that is in the silo outside. has anyone tried to launch it, and what did it do, i was afraid i would blow up something important.lol

Lol. I saw that the first time I entered, and decided to launch it. Spoiler, if you want to go back and try it yourself:

LMAO i would have reacted the same way