[Mayday]

I like to max out my intel and have One level 3 Counter-Intelligence running, and the rest all Puppet Political Parties. Works a treat on less espionage oriented people, especially during a war.
Sometimes they join me, sometimes they make their own governments, all the time they get totally glassed by their former rulers.
And when that stops working, I change it to have one level 3 Counter-Int and all the rest are Crew Insurgents. I tend to take over most of their fleets with little work, and glass whatever is left.

[Edit]
I should also mention that they're all completed in one turn, and I have it set to repeat projects. That's how much much I'll put into it. With that much, I can bankrupt most factions.