How I think they got it is where I might differ from most others.
With the exception of Roswell where I think its obvious something out of the ordinary happened, I'm much more inclined to believe they found tech on either the moon or Mars.
Space exploration stinks of lies and coverups, why? Because either they faked some of it, or....they were looking for something and found it. Also, if I were an alien and I wanted to view/study the silly humans I'd park myself on the moon. That would likely mean I'd leave stuff there when I left, and considering how long the earth has had humans running around on its surface I think its more than lkely they HAVE watched us.
Do I believe theres intelligent life in the universe? Well, I think even our own galaxy is teeming with it. Its just so BIG out there it'll take us a long time to find each other, and when we/they do find life elsewhere it makes sense to quietly observe for a while before saying hello.
Great idea for a thread
ETA: I dont believe that a lot of the tech we ordinary folke see has anything to do with alien tech, I often see people claiming that transistors and silicone chips were given to us by aliens, thats complete bs, I've been into electronics as a hobby for many many years and I saw the evolution from valves/tubes to early transisters and chips, nothing at all to do with aliens.
edit on 28-11-2012 by VoidHawk because: (no reason given)