Let's say the Gaians have this one base (not the HQ) with 3 secret projects.
Just make a new base, and trade the size 1 base for her size 14 base with 
those secret projects! Sound too good to be true? Hansen has some reassurance
for the critics. "Everytime I have offered to trade base for base, the leader
agrees without getting mad. Not only have I used this to get all the secret 
projects I've missed ([all the while] hoping they don't build them in HQ), 
I've used this method to completely bring down empires in peacetime. Just 
build a random colony in the middle of nowhere, and trade it for an ally's
size 15 base.