A few days ago (sorry couldn't find the original post in all the clutter) there was a suggestion that you could move some war-ships and a constructor near a starbase owned by one alien, give the war-ships to another alien with which the first alien was at war, and the second alien would then promptly use the gifted ships to destroy the starbase, letting you move in with your constructor to take the resource.
Sorry, doesn't (always) work. I tried it twice against the Drengin, by giving the warring Torians a couple of SWEET destroyers (large hull ships). Oddly enough, the Torian not only didn't smear the starbase for me, but he was also too stupid (and this is at 'Painful" AI) to group the destroyers together and so lost them a couple of turns later by using them one-at-a-time to attack a group of Drengin fighters. I was so mad I gave the Drengin 10,000 credits and my blessing to eat some tasty green skin.
Really, this isn't a rant, but fair warning... the dirty trick isn't so great after all. Happy conquering!